docs: def _get_pitch(self, soup, pa):
          """
          get pitch data
          :param soup: Beautifulsoup object
          :param pa: atbat data for plate appearance
          :return: pitches result(list)
          """
          pitches = []
          ball_tally, strike_tally = 0, 0
          for pitch in soup.find_all('pitch'):
              # pitching result
              pitch = Pitch.row(pitch, pa, pitches, ball_tally, strike_tally)
              pitches.append(pitch)
              # ball count
              ball_tally, strike_tally = RetroSheet.ball_count(ball_tally, strike_tally, pitch['pitch_res'])
          return pitches