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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 drop_index(self, keep_model=True):
 """Drop all indexed documents from the session. Optionally, drop model too."""

        self.check_session()
        result = self.session.drop_index(keep_model)
        if self.autosession:
            self.commit()
        return result