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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_in_hdx(self):
 # type: () -> None """Check if user exists in HDX and if so, update user Returns: None """

        capacity = self.data.get('capacity')
        if capacity is not None:
            del self.data['capacity']  # remove capacity (which comes from users from Organization)
        self._update_in_hdx('user', 'id')
        if capacity is not None:
            self.data['capacity'] = capacity