mesh_looptools.py

        # move vertices to new locations
        move_verts(mesh, mapping, move, self.influence)
        
        # cleaning up 
        if derived:
            bpy.context.blend_data.meshes.remove(mesh_mod)
        
        terminate(global_undo)
        return{'FINISHED'}


# flatten operator
class Flatten(bpy.types.Operator):
    bl_idname = "mesh.looptools_flatten"
    bl_label = "Flatten"
    bl_description = "Flatten vertices on a best-fitting plane"
    bl_options = {'REGISTER', 'UNDO'}
    
    influence = bpy.props.FloatProperty(name = "Influence",
        description = "Force of the tool",
        default = 100.0,
        min = 0.0,
        max = 100.0,
        precision = 1,
        subtype = 'PERCENTAGE')
    plane = bpy.props.EnumProperty(name = "Plane",
        items = (("best_fit", "Best fit", "Calculate a best fitting plane"),
            ("normal", "Normal", "Derive plane from averaging vertex "\
            "normals"),
            ("view", "View", "Flatten on a plane perpendicular to the "\
            "viewing angle")),
        description = "Plane on which vertices are flattened",
        default = 'best_fit')
    restriction = bpy.props.EnumProperty(name = "Restriction",
        items = (("none", "None", "No restrictions on vertex movement"),
            ("bounding_box", "Bounding box", "Vertices are restricted to "\
            "movement inside the bounding box of the selection")),
        description = "Restrictions on how the vertices can be moved",
        default = 'none')
    
    @classmethod
    def poll(cls, context):
        ob = context.active_object
        return(ob and ob.type == 'MESH' and context.mode == 'EDIT_MESH')
    
    def draw(self, context):
        layout = self.layout
        col = layout.column()
        
        col.prop(self, "plane")
        #col.prop(self, "restriction")
        col.separator()
        
        col.prop(self, "influence")
    
    def invoke(self, context, event):
        # load custom settings
        settings_load(self)
        return self.execute(context)
    
    def execute(self, context):
        # initialise
        global_undo, object, mesh = initialise()
        settings_write(self)
        # check cache to see if we can save time
        cached, single_loops, loops, derived, mapping = cache_read("Flatten",
            object, mesh, False, False)
        if not cached:
            # order input into virtual loops
            loops = flatten_get_input(mesh)
            loops = check_loops(loops, mapping, mesh)
        
        # saving cache for faster execution next time
        if not cached:
            cache_write("Flatten", object, mesh, False, False, False, loops,
                False, False)
        
        move = []
        for loop in loops:
            # calculate plane and position of vertices on them
            com, normal = calculate_plane(mesh, loop, method=self.plane,
                object=object)
            to_move = flatten_project(mesh, loop, com, normal)
            if self.restriction == 'none':
                move.append(to_move)
            else:
                move.append(to_move)
        move_verts(mesh, False, move, self.influence)
        
        terminate(global_undo)
        return{'FINISHED'}


# relax operator
class Relax(bpy.types.Operator):
    bl_idname = "mesh.looptools_relax"
    bl_label = "Relax"
    bl_description = "Relax the loop, so it is smoother"
    bl_options = {'REGISTER', 'UNDO'}
    
    input = bpy.props.EnumProperty(name = "Input",
        items = (("all", "Parallel (all)", "Also use non-selected "\
                "parallel loops as input"),
            ("selected", "Selection","Only use selected vertices as input")),
        description = "Loops that are relaxed",
        default = 'selected')
    interpolation = bpy.props.EnumProperty(name = "Interpolation",
        items = (("cubic", "Cubic", "Natural cubic spline, smooth results"),
            ("linear", "Linear", "Simple and fast linear algorithm")),
        description = "Algorithm used for interpolation",
        default = 'cubic')
    iterations = bpy.props.EnumProperty(name = "Iterations",
        items = (("1", "1", "One"),
            ("3", "3", "Three"),
            ("5", "5", "Five"),
            ("10", "10", "Ten"),
            ("25", "25", "Twenty-five")),
        description = "Number of times the loop is relaxed",
        default = "1")
    regular = bpy.props.BoolProperty(name = "Regular",
        description = "Distribute vertices at constant distances along the" \
            "loop",
        default = True)
    
    @classmethod
    def poll(cls, context):
        ob = context.active_object
        return(ob and ob.type == 'MESH' and context.mode == 'EDIT_MESH')
    
    def draw(self, context):
        layout = self.layout
        col = layout.column()
        
        col.prop(self, "interpolation")
        col.prop(self, "input")
        col.prop(self, "iterations")
        col.prop(self, "regular")
    
    def invoke(self, context, event):
        # load custom settings
        settings_load(self)
        return self.execute(context)
    
    def execute(self, context):
        # initialise
        global_undo, object, mesh = initialise()
        settings_write(self)
        # check cache to see if we can save time
        cached, single_loops, loops, derived, mapping = cache_read("Relax",
            object, mesh, self.input, False)
        if cached:
            derived, mesh_mod = get_derived_mesh(object, mesh, context.scene)
        else:
            # find loops
            derived, mesh_mod, loops = get_connected_input(object, mesh,
                context.scene, self.input)
            mapping = get_mapping(derived, mesh, mesh_mod, False, False, loops)
            loops = check_loops(loops, mapping, mesh_mod)
        knots, points = relax_calculate_knots(loops)
        
        # saving cache for faster execution next time
        if not cached:
            cache_write("Relax", object, mesh, self.input, False, False, loops,
                derived, mapping)
        
        for iteration in range(int(self.iterations)):
            # calculate splines and new positions
            tknots, tpoints = relax_calculate_t(mesh_mod, knots, points,
                self.regular)
            splines = []
            for i in range(len(knots)):
                splines.append(calculate_splines(self.interpolation, mesh_mod,
                    tknots[i], knots[i]))
            move = [relax_calculate_verts(mesh_mod, self.interpolation,
                tknots, knots, tpoints, points, splines)]
            move_verts(mesh, mapping, move, -1)
        
        # cleaning up 
        if derived:
            bpy.context.blend_data.meshes.remove(mesh_mod)
        terminate(global_undo)
        
        return{'FINISHED'}


# space operator
class Space(bpy.types.Operator):
    bl_idname = "mesh.looptools_space"
    bl_label = "Space"
    bl_description = "Space the vertices in a regular distrubtion on the loop"
    bl_options = {'REGISTER', 'UNDO'}
    
    influence = bpy.props.FloatProperty(name = "Influence",
        description = "Force of the tool",
        default = 100.0,
        min = 0.0,
        max = 100.0,
        precision = 1,
        subtype = 'PERCENTAGE')
    input = bpy.props.EnumProperty(name = "Input",
        items = (("all", "Parallel (all)", "Also use non-selected "\
                "parallel loops as input"),
            ("selected", "Selection","Only use selected vertices as input")),
        description = "Loops that are spaced",
        default = 'selected')
    interpolation = bpy.props.EnumProperty(name = "Interpolation",
        items = (("cubic", "Cubic", "Natural cubic spline, smooth results"),
            ("linear", "Linear", "Vertices are projected on existing edges")),
        description = "Algorithm used for interpolation",
        default = 'cubic')
    
    @classmethod
    def poll(cls, context):
        ob = context.active_object
        return(ob and ob.type == 'MESH' and context.mode == 'EDIT_MESH')
    
    def draw(self, context):
        layout = self.layout
        col = layout.column()
        
        col.prop(self, "interpolation")
        col.prop(self, "input")
        col.separator()
        
        col.prop(self, "influence")
    
    def invoke(self, context, event):
        # load custom settings
        settings_load(self)
        return self.execute(context)
    
    def execute(self, context):
        # initialise
        global_undo, object, mesh = initialise()
        settings_write(self)
        # check cache to see if we can save time
        cached, single_loops, loops, derived, mapping = cache_read("Space",
            object, mesh, self.input, False)
        if cached:
            derived, mesh_mod = get_derived_mesh(object, mesh, context.scene)
        else:
            # find loops
            derived, mesh_mod, loops = get_connected_input(object, mesh,
                context.scene, self.input)
            mapping = get_mapping(derived, mesh, mesh_mod, False, False, loops)
            loops = check_loops(loops, mapping, mesh_mod)
        
        # saving cache for faster execution next time
        if not cached:
            cache_write("Space", object, mesh, self.input, False, False, loops,
                derived, mapping)
        
        move = []
        for loop in loops:
            # calculate splines and new positions
            if loop[1]: # circular
                loop[0].append(loop[0][0])
            tknots, tpoints = space_calculate_t(mesh_mod, loop[0][:])
            splines = calculate_splines(self.interpolation, mesh_mod,
                tknots, loop[0][:])
            move.append(space_calculate_verts(mesh_mod, self.interpolation,
                tknots, tpoints, loop[0][:-1], splines))
        
        # move vertices to new locations
        move_verts(mesh, mapping, move, self.influence)
        
        # cleaning up 
        if derived:
            bpy.context.blend_data.meshes.remove(mesh_mod)
        terminate(global_undo)
        
        return{'FINISHED'}


##########################################
####### GUI and registration #############
##########################################

# menu containing all tools
class VIEW3D_MT_edit_mesh_looptools(bpy.types.Menu):
    bl_label = "LoopTools"
    
    def draw(self, context):
        layout = self.layout
        
        layout.operator("mesh.looptools_bridge", text="Bridge").loft = False
        layout.operator("mesh.looptools_circle")
        layout.operator("mesh.looptools_curve")
        layout.operator("mesh.looptools_flatten")
        layout.operator("mesh.looptools_bridge", text="Loft").loft = True
        layout.operator("mesh.looptools_relax")
        layout.operator("mesh.looptools_space")


# panel containing all tools
class VIEW3D_PT_tools_looptools(bpy.types.Panel):
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'TOOLS'
    bl_context = "mesh_edit"
    bl_label = "LoopTools"

    def draw(self, context):
        layout = self.layout
        col = layout.column(align=True)
        lt = context.window_manager.looptools
        
        # bridge - first line
        split = col.split(percentage=0.15)
        if lt.display_bridge:
            split.prop(lt, "display_bridge", text="", icon='DOWNARROW_HLT')
        else:
            split.prop(lt, "display_bridge", text="", icon='RIGHTARROW')
        split.operator("mesh.looptools_bridge", text="Bridge").loft = False
        # bridge - settings
        if lt.display_bridge:
            box = col.column(align=True).box().column()
            #box.prop(self, "mode")
            
            # top row
            col_top = box.column(align=True)
            row = col_top.row(align=True)
            col_left = row.column(align=True)
            col_right = row.column(align=True)
            col_right.active = lt.bridge_segments != 1
            col_left.prop(lt, "bridge_segments")
            col_right.prop(lt, "bridge_min_width", text="")
            # bottom row
            bottom_left = col_left.row()
            bottom_left.active = lt.bridge_segments != 1
            bottom_left.prop(lt, "bridge_interpolation", text="")
            bottom_right = col_right.row()
            bottom_right.active = lt.bridge_interpolation == 'cubic'
            bottom_right.prop(lt, "bridge_cubic_strength")
            # boolean properties
            col_top.prop(lt, "bridge_remove_faces")
            
            # override properties
            col_top.separator()
            row = box.row(align = True)
            row.prop(lt, "bridge_twist")
            row.prop(lt, "bridge_reverse")
        
        # circle - first line
        split = col.split(percentage=0.15)
        if lt.display_circle:
            split.prop(lt, "display_circle", text="", icon='DOWNARROW_HLT')
        else:
            split.prop(lt, "display_circle", text="", icon='RIGHTARROW')
        split.operator("mesh.looptools_circle")
        # circle - settings
        if lt.display_circle:
            box = col.column(align=True).box().column()
            box.prop(lt, "circle_fit")
            box.separator()
            
            box.prop(lt, "circle_flatten")
            row = box.row(align=True)
            row.prop(lt, "circle_custom_radius")
            row_right = row.row(align=True)
            row_right.active = lt.circle_custom_radius
            row_right.prop(lt, "circle_radius", text="")
            box.prop(lt, "circle_regular")
            box.separator()
            
            box.prop(lt, "circle_influence")
        
        # curve - first line
        split = col.split(percentage=0.15)
        if lt.display_curve:
            split.prop(lt, "display_curve", text="", icon='DOWNARROW_HLT')
        else:
            split.prop(lt, "display_curve", text="", icon='RIGHTARROW')
        split.operator("mesh.looptools_curve")
        # curve - settings
        if lt.display_curve:
            box = col.column(align=True).box().column()
            box.prop(lt, "curve_interpolation")
            box.prop(lt, "curve_restriction")
            box.prop(lt, "curve_boundaries")
            box.prop(lt, "curve_regular")
            box.separator()
            
            box.prop(lt, "curve_influence")
        
        # flatten - first line
        split = col.split(percentage=0.15)
        if lt.display_flatten:
            split.prop(lt, "display_flatten", text="", icon='DOWNARROW_HLT')
        else:
            split.prop(lt, "display_flatten", text="", icon='RIGHTARROW')
        split.operator("mesh.looptools_flatten")
        # flatten - settings
        if lt.display_flatten:
            box = col.column(align=True).box().column()
            box.prop(lt, "flatten_plane")
            #box.prop(lt, "flatten_restriction")
            box.separator()
            
            box.prop(lt, "flatten_influence")
        
        # loft - first line
        split = col.split(percentage=0.15)
        if lt.display_loft:
            split.prop(lt, "display_loft", text="", icon='DOWNARROW_HLT')
        else:
            split.prop(lt, "display_loft", text="", icon='RIGHTARROW')
        split.operator("mesh.looptools_bridge", text="Loft").loft = True
        # loft - settings
        if lt.display_loft:
            box = col.column(align=True).box().column()
            #box.prop(self, "mode")
            
            # top row
            col_top = box.column(align=True)
            row = col_top.row(align=True)
            col_left = row.column(align=True)
            col_right = row.column(align=True)
            col_right.active = lt.bridge_segments != 1
            col_left.prop(lt, "bridge_segments")
            col_right.prop(lt, "bridge_min_width", text="")
            # bottom row
            bottom_left = col_left.row()
            bottom_left.active = lt.bridge_segments != 1
            bottom_left.prop(lt, "bridge_interpolation", text="")
            bottom_right = col_right.row()
            bottom_right.active = lt.bridge_interpolation == 'cubic'
            bottom_right.prop(lt, "bridge_cubic_strength")
            # boolean properties
            col_top.prop(lt, "bridge_remove_faces")
            col_top.prop(lt, "bridge_loft_loop")
            
            # override properties
            col_top.separator()
            row = box.row(align = True)
            row.prop(lt, "bridge_twist")
            row.prop(lt, "bridge_reverse")
        
        # relax - first line
        split = col.split(percentage=0.15)
        if lt.display_relax:
            split.prop(lt, "display_relax", text="", icon='DOWNARROW_HLT')
        else:
            split.prop(lt, "display_relax", text="", icon='RIGHTARROW')
        split.operator("mesh.looptools_relax")
        # relax - settings
        if lt.display_relax:
            box = col.column(align=True).box().column()
            box.prop(lt, "relax_interpolation")
            box.prop(lt, "relax_input")
            box.prop(lt, "relax_iterations")
            box.prop(lt, "relax_regular")
        
        # space - first line
        split = col.split(percentage=0.15)
        if lt.display_space:
            split.prop(lt, "display_space", text="", icon='DOWNARROW_HLT')
        else:
            split.prop(lt, "display_space", text="", icon='RIGHTARROW')
        split.operator("mesh.looptools_space")
        # space - settings
        if lt.display_space:
            box = col.column(align=True).box().column()
            box.prop(lt, "space_interpolation")
            box.prop(lt, "space_input")
            box.separator()
            
            box.prop(lt, "space_influence")


# property group containing all properties for the gui in the panel
class LoopToolsProps(bpy.types.PropertyGroup):
    """
    Fake module like class
    bpy.context.window_manager.looptools
    """
    
    # general display properties
    display_bridge = bpy.props.BoolProperty(name = "Bridge settings",
        description = "Display settings of the Bridge tool",
        default = False)
    display_circle = bpy.props.BoolProperty(name = "Circle settings",
        description = "Display settings of the Circle tool",
        default = False)
    display_curve = bpy.props.BoolProperty(name = "Curve settings",
        description = "Display settings of the Curve tool",
        default = False)
    display_flatten = bpy.props.BoolProperty(name = "Flatten settings",
        description = "Display settings of the Flatten tool",
        default = False)
    display_loft = bpy.props.BoolProperty(name = "Loft settings",
        description = "Display settings of the Loft tool",
        default = False)
    display_relax = bpy.props.BoolProperty(name = "Relax settings",
        description = "Display settings of the Relax tool",
        default = False)
    display_space = bpy.props.BoolProperty(name = "Space settings",
        description = "Display settings of the Space tool",
        default = False)
    
    # bridge properties
    bridge_cubic_strength = bpy.props.FloatProperty(name = "Strength",
        description = "Higher strength results in more fluid curves",
        default = 1.0,
        soft_min = -3.0,
        soft_max = 3.0)
    bridge_interpolation = bpy.props.EnumProperty(name = "Interpolation mode",
        items = (('cubic', "Cubic", "Gives curved results"),
            ('linear', "Linear", "Basic, fast, straight interpolation")),
        description = "Interpolation mode: algorithm used when creating "\
            "segments",
        default = 'cubic')
    bridge_loft = bpy.props.BoolProperty(name = "Loft",
        description = "Loft multiple loops, instead of considering them as "\
            "a multi-input for bridging",
        default = False)
    bridge_loft_loop = bpy.props.BoolProperty(name = "Loop",
        description = "Connect the first and the last loop with each other",
        default = False)
    bridge_min_width = bpy.props.IntProperty(name = "Minimum width",
        description = "Segments with an edge smaller than this are merged "\
            "(compared to base edge)",
        default = 0,
        min = 0,
        max = 100,
        subtype = 'PERCENTAGE')
    bridge_mode = bpy.props.EnumProperty(name = "Mode",
        items = (('basic', "Basic", "Fast algorithm"), ('shortest',
            "Shortest edge", "Slower algorithm with better vertex matching")),
        description = "Algorithm used for bridging",
        default = 'shortest')
    bridge_remove_faces = bpy.props.BoolProperty(name = "Remove faces",
        description = "Remove faces that are internal after bridging",
        default = True)
    bridge_reverse = bpy.props.BoolProperty(name = "Reverse",
        description = "Manually override the direction in which the loops "\
            "are bridged. Only use if the tool gives the wrong result.",
        default = False)
    bridge_segments = bpy.props.IntProperty(name = "Segments",
        description = "Number of segments used to bridge the gap "\
            "(0 = automatic)",
        default = 1,
        min = 0,
        soft_max = 20)
    bridge_twist = bpy.props.IntProperty(name = "Twist",
        description = "Twist what vertices are connected to each other",
        default = 0)
    
    # circle properties
    circle_custom_radius = bpy.props.BoolProperty(name = "Radius",
        description = "Force a custom radius",
        default = False)
    circle_fit = bpy.props.EnumProperty(name = "Method",
        items = (("best", "Best fit", "Non-linear least squares"),
            ("inside", "Fit inside","Only move vertices towards the center")),
        description = "Method used for fitting a circle to the vertices",
        default = 'best')
    circle_flatten = bpy.props.BoolProperty(name = "Flatten",
        description = "Flatten the circle, instead of projecting it on the " \
            "mesh",
        default = True)
    circle_influence = bpy.props.FloatProperty(name = "Influence",
        description = "Force of the tool",
        default = 100.0,
        min = 0.0,
        max = 100.0,
        precision = 1,
        subtype = 'PERCENTAGE')
    circle_radius = bpy.props.FloatProperty(name = "Radius",
        description = "Custom radius for circle",
        default = 1.0,
        min = 0.0,
        soft_max = 1000.0)
    circle_regular = bpy.props.BoolProperty(name = "Regular",
        description = "Distribute vertices at constant distances along the " \
            "circle",
        default = True)
    
    # curve properties
    curve_boundaries = bpy.props.BoolProperty(name = "Boundaries",
        description = "Limit the tool to work within the boundaries of the "\
            "selected vertices",
        default = False)
    curve_influence = bpy.props.FloatProperty(name = "Influence",
        description = "Force of the tool",
        default = 100.0,
        min = 0.0,
        max = 100.0,
        precision = 1,
        subtype = 'PERCENTAGE')
    curve_interpolation = bpy.props.EnumProperty(name = "Interpolation",
        items = (("cubic", "Cubic", "Natural cubic spline, smooth results"),
            ("linear", "Linear", "Simple and fast linear algorithm")),
        description = "Algorithm used for interpolation",
        default = 'cubic')
    curve_regular = bpy.props.BoolProperty(name = "Regular",
        description = "Distribute vertices at constant distances along the" \
            "curve",
        default = True)
    curve_restriction = bpy.props.EnumProperty(name = "Restriction",
        items = (("none", "None", "No restrictions on vertex movement"),
            ("extrude", "Extrude only","Only allow extrusions (no "\
                "indentations)"),
            ("indent", "Indent only", "Only allow indentation (no "\
                "extrusions)")),
        description = "Restrictions on how the vertices can be moved",
        default = 'none')
    
    # flatten properties
    flatten_influence = bpy.props.FloatProperty(name = "Influence",
        description = "Force of the tool",
        default = 100.0,
        min = 0.0,
        max = 100.0,
        precision = 1,
        subtype = 'PERCENTAGE')
    flatten_plane = bpy.props.EnumProperty(name = "Plane",
        items = (("best_fit", "Best fit", "Calculate a best fitting plane"),
            ("normal", "Normal", "Derive plane from averaging vertex "\
            "normals"),
            ("view", "View", "Flatten on a plane perpendicular to the "\
            "viewing angle")),
        description = "Plane on which vertices are flattened",
        default = 'best_fit')
    flatten_restriction = bpy.props.EnumProperty(name = "Restriction",
        items = (("none", "None", "No restrictions on vertex movement"),
            ("bounding_box", "Bounding box", "Vertices are restricted to "\
            "movement inside the bounding box of the selection")),
        description = "Restrictions on how the vertices can be moved",
        default = 'none')
    
    # relax properties
    relax_input = bpy.props.EnumProperty(name = "Input",
        items = (("all", "Parallel (all)", "Also use non-selected "\
                "parallel loops as input"),
            ("selected", "Selection","Only use selected vertices as input")),
        description = "Loops that are relaxed",
        default = 'selected')
    relax_interpolation = bpy.props.EnumProperty(name = "Interpolation",
        items = (("cubic", "Cubic", "Natural cubic spline, smooth results"),
            ("linear", "Linear", "Simple and fast linear algorithm")),
        description = "Algorithm used for interpolation",
        default = 'cubic')
    relax_iterations = bpy.props.EnumProperty(name = "Iterations",
        items = (("1", "1", "One"),
            ("3", "3", "Three"),
            ("5", "5", "Five"),
            ("10", "10", "Ten"),
            ("25", "25", "Twenty-five")),
        description = "Number of times the loop is relaxed",
        default = "1")
    relax_regular = bpy.props.BoolProperty(name = "Regular",
        description = "Distribute vertices at constant distances along the" \
            "loop",
        default = True)
    
    # space properties
    space_influence = bpy.props.FloatProperty(name = "Influence",
        description = "Force of the tool",
        default = 100.0,
        min = 0.0,
        max = 100.0,
        precision = 1,
        subtype = 'PERCENTAGE')
    space_input = bpy.props.EnumProperty(name = "Input",
        items = (("all", "Parallel (all)", "Also use non-selected "\
                "parallel loops as input"),
            ("selected", "Selection","Only use selected vertices as input")),
        description = "Loops that are spaced",
        default = 'selected')
    space_interpolation = bpy.props.EnumProperty(name = "Interpolation",
        items = (("cubic", "Cubic", "Natural cubic spline, smooth results"),
            ("linear", "Linear", "Vertices are projected on existing edges")),
        description = "Algorithm used for interpolation",
        default = 'cubic')


# draw function for integration in menus
def menu_func(self, context):
    self.layout.menu("VIEW3D_MT_edit_mesh_looptools")
    self.layout.separator()


# define classes for registration
classes = [VIEW3D_MT_edit_mesh_looptools,
    VIEW3D_PT_tools_looptools,
    LoopToolsProps,
    Bridge,
    Circle,
    Curve,
    Flatten,
    Relax,
    Space]


# registering and menu integration
def register():
    for c in classes:
        bpy.utils.register_class(c)
    bpy.types.VIEW3D_MT_edit_mesh_specials.prepend(menu_func)
    bpy.types.WindowManager.looptools = bpy.props.PointerProperty(\
        type = LoopToolsProps)


# unregistering and removing menus
def unregister():
    for c in classes:
        bpy.utils.unregister_class(c)
    bpy.types.VIEW3D_MT_edit_mesh_specials.remove(menu_func)
    try:
        del bpy.types.WindowManager.looptools
    except:
        pass


if __name__ == "__main__":
    register()