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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 multiply(x1, x2, output_shape=None, name=None):
 """Binary multiplication with broadcasting. Args: x1: a Tensor x2: a Tensor output_shape: an optional Shape name: an optional string Returns: a Tensor """

  if not isinstance(x2, Tensor):
    return ScalarMultiplyOperation(x1, x2).outputs[0]
  with tf.name_scope(name, default_name="mul"):
    x1, x2 = binary_arguments_to_tensors(x1, x2)
    return einsum(
        [x1, x2],
        output_shape=_infer_binary_broadcast_shape(
            x1.shape, x2.shape, output_shape))