code: def matches(self, other):
          
          return self.interaction == other.interaction and \
              self.direction != other.direction and \
              self.call_duration == other.call_duration and \
              abs((self.datetime - other.datetime).total_seconds()) < 30
docs: Return true if two records 'match': if they share the same values for
          ``interaction``, ``direction``, ``call_duration``, and ``datetime``.