code: def _get_usage(self, account_number, number):
          
          # Prepare data
          data = {"ctn": number,
                  "language": "en-US",
                  "accountNumber": account_number}
          # Http request
          try:
              raw_res = yield from self._session.post(USAGE_URL,
                                                      data=data,
                                                      headers=self._headers,
                                                      timeout=self._timeout)
          except OSError:
              raise PyFidoError("Can not get usage")
          # Load answer as json
          try:
              output = yield from raw_res.json()
          except (OSError, ValueError):
              raise PyFidoError("Can not get usage as json")
          # Format data
          ret_data = {}
          for data_name, keys in DATA_MAP.items():
              key, subkey = keys
              for data in output.get(key)[0].get('wirelessUsageSummaryInfoList'):
                  if data.get('usageSummaryType') == subkey:
                      # Prepare keys:
                      used_key = "{}_used".format(data_name)
                      remaining_key = "{}_remaining".format(data_name)
                      limit_key = "{}_limit".format(data_name)
                      # Get values
                      ret_data[used_key] = data.get('used', 0.0)
                      if data.get('remaining') >= 0:
                          ret_data[remaining_key] = data.get('remaining')
                      else:
                          ret_data[remaining_key] = None
                      if data.get('total') >= 0:
                          ret_data[limit_key] = data.get('total')
                      else:
                          ret_data[limit_key] = None
  
          return ret_data
docs: Get Fido usage.
  
          Get the following data
          - talk
          - text
          - data
  
          Roaming data is not supported yet