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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 is_valid_assignment(self, mtf_dimension_name, mesh_dimension_name):
 """Whether this MTF dimension may be assigned to this mesh dimension. Args: mtf_dimension_name: string, the name of a Mesh TensorFlow dimension. mesh_dimension_name: string, the name of a mesh dimension. Returns: A boolean indicating whether the assignment is valid. """

    return ((mtf_dimension_name in self._splittable_mtf_dimension_names) and
            (self._mtf_dimension_name_to_size_gcd[mtf_dimension_name] %
             self._mesh_dimension_name_to_size[mesh_dimension_name] == 0))