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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def merge_vertices(self, digits=None, textured=True):
 """ If a mesh has vertices that are closer than trimesh.constants.tol.merge reindex faces to reference the same index for both vertices. Parameters digits : int If specified overrides tol.merge textured : bool If True avoids merging vertices with different UV coordinates. No effect on untextured meshes. """

        grouping.merge_vertices(self,
                                digits=digits,
                                textured=textured)