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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 mtf_range(mesh, dim, dtype, name=None):
 """Create a 1d mesh tensor with a range from [0, dim.size). Call externally as mtf.range() Args: mesh: a Mesh dim: a Dimension dtype: a tf.DType name: an optional string Returns: a Tensor """

  dim = convert_to_dimension(dim)
  with tf.variable_scope(name, default_name="range"):
    if dtype == tf.bfloat16:
      # tf.range(dtype=bfloat16) gives the wrong shape.
      # TODO(noam): report the bug.
      tf_range = tf.cast(tf.range(dim.size), tf.bfloat16)
    else:
      tf_range = tf.range(dim.size, dtype=dtype)
    return import_tf_tensor(mesh, tf_range, shape=Shape([dim]))