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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 processor_coordinates_to_pnum(mesh_shape, coord):
 """Inverse of pnum_to_processor_coordinates. Args: mesh_shape: a Shape coord: a list of integers with length len(mesh_shape) Returns: an integer less than len(mesh_shape) """

  ret = 0
  multiplier = 1
  for c, d in zip(coord[::-1], mesh_shape.to_integer_list[::-1]):
    ret += multiplier * c
    multiplier *= d
  return ret