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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 set_dimension(tensor, axis, value):
 """Set the length of a tensor along the specified dimension. Args: tensor: Tensor to define shape of. axis: Dimension to set the static shape for. value: Integer holding the length. Raises: ValueError: When the tensor already has a different length specified. """

  shape = tensor.shape.as_list()
  if shape[axis] not in (value, None):
    message = 'Cannot set dimension {} of tensor {} to {}; is already {}.'
    raise ValueError(message.format(axis, tensor.name, value, shape[axis]))
  shape[axis] = value
  tensor.set_shape(shape)