Generates the names of all input tensors of an operation.

    Args:
      operation_name: a string, the name of an operation in the graph.

    Yields:
      a string, the name of an input tensor.

def get_operation_input_names(self, operation_name):
    """Generates the names of all input tensors of an operation.

    Args:
      operation_name: a string, the name of an operation in the graph.

    Yields:
      a string, the name of an input tensor.
    """
    for input_tensor in self._name_to_operation(operation_name).inputs:
      yield input_tensor.name