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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 _get_reference_namespace(self, name):
 """ Return namespace where reference name is defined It returns the globals() if reference has not yet been defined """

        glbs = self._mglobals()
        if self._pdb_frame is None:
            return glbs
        else:
            lcls = self._pdb_locals
            if name in lcls:
                return lcls
            else:
                return glbs