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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 to_dict(self):
 """Return a dict representing the ChemicalEntity that can be read back using from_dict. """

        
        ret = merge_dicts(self.__attributes__, self.__relations__, self.__fields__)
        ret = {k : v.value for k,v in ret.items()}
        ret['maps'] = {k : v.value for k,v in self.maps.items()}
        return ret