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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 update_type_lookups(self):
 """ Update type and typestring lookup dicts. Must be called once the ``types`` and ``python_type_strings`` attributes are set so that ``type_to_typestring`` and ``typestring_to_type`` are constructed. .. versionadded:: 0.2 Notes ----- Subclasses need to call this function explicitly. """

        self.type_to_typestring = dict(zip(self.types,
                                           self.python_type_strings))
        self.typestring_to_type = dict(zip(self.python_type_strings,
                                           self.types))