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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_user_id(self, mxit_id, scope='profile/public'):
 """ Retrieve the Mxit user's internal "user ID" No user authentication required """

        user_id = _get(
            token=self.oauth.get_app_token(scope),
            uri='/user/lookup/' + urllib.quote(mxit_id)
        )

        if user_id.startswith('"') and user_id.endswith('"'):
            user_id = user_id[1:-1]

        return user_id