code: def is_in_coverage(unixtime, weathers_list):
      
      if not weathers_list:
          return False
      else:
          min_of_coverage = min([weather.get_reference_time() \
                                 for weather in weathers_list])
          max_of_coverage = max([weather.get_reference_time() \
                                 for weather in weathers_list])
          if unixtime < min_of_coverage or unixtime > max_of_coverage:
              return False
          return True
docs: Checks if the supplied UNIX time is contained into the time range
      (coverage) defined by the most ancient and most recent *Weather* objects
      in the supplied list
  
      :param unixtime: the UNIX time to be searched in the time range
      :type unixtime: int
      :param weathers_list: the list of *Weather* objects to be scanned for
          global time coverage
      :type weathers_list: list
      :returns: ``True`` if the UNIX time is contained into the time range,
          ``False`` otherwise