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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 _GetFlowArgsHelpAsString(self, flow_cls):
 """Get a string description of the calling prototype for this flow."""

    output = [
        "  Call Spec:",
        "    %s" % self._GetCallingPrototypeAsString(flow_cls), ""
    ]
    arg_list = sorted(
        iteritems(self._GetArgsDescription(flow_cls.args_type)),
        key=lambda x: x[0])
    if not arg_list:
      output.append("  Args: None")
    else:
      output.append("  Args:")
      for arg, val in arg_list:
        output.append("    %s" % arg)
        output.append("      description: %s" % val["description"])
        output.append("      type: %s" % val["type"])
        output.append("      default: %s" % val["default"])
        output.append("")
    return "\n".join(output)