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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 subGraphHasField(self, parent_name, graph_name, field_name):
 """Return true if subgraph with name graph_name with parent graph with name parent_name has field with name field_name. @param parent_name: Root Graph Name @param graph_name: Subgraph Name @param field_name: Field Name. @return: Boolean """

        subgraph = self._getSubGraph(parent_name, graph_name, True)
        return subgraph.hasField(field_name)