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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 _local_var_name(splittable_dimensions, assignment):
 """Name for a local variable. Args: splittable_dimensions: frozenset of names of splittable dimensions. assignment: dict from names of splittable dimensions to names of mesh dimensions. Returns: A string, the variable name. """

  assignment_string = []
  for splittable in sorted(splittable_dimensions):
    if splittable in assignment:
      assignment_string.append("{}:{}".format(splittable,
                                              assignment[splittable]))
    else:
      assignment_string.append("{}".format(splittable))
  return "y_(" + ",".join(assignment_string) + ")"