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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_default_calendar(self):
 """ Returns the default calendar for the current user :rtype: Calendar """


        url = self.build_url(self._endpoints.get('default_calendar'))

        response = self.con.get(url)
        if not response:
            return None

        data = response.json()

        # Everything received from cloud must be passed as self._cloud_data_key
        return self.calendar_constructor(parent=self,
                                         **{self._cloud_data_key: data})