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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 new_calendar(self, calendar_name):
 """ Creates a new calendar :param str calendar_name: name of the new calendar :return: a new Calendar instance :rtype: Calendar """

        if not calendar_name:
            return None

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

        response = self.con.post(url, data={self._cc('name'): calendar_name})
        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})