code: def from_gtp(gtpc):
      
      gtpc = gtpc.upper()
      if gtpc == 'PASS':
          return None
      col = _GTP_COLUMNS.index(gtpc[0])
      row_from_bottom = int(gtpc[1:])
      return go.N - row_from_bottom, col
docs: Converts from a GTP coordinate to a Minigo coordinate.