def ss_to_index(ss):
 if (ss == 'H'):
  return 0
 if (ss == 'E'):
  return 1
 if (ss == 'C'):
  return 2
 assert 0

def ss_to_index ( ss ) : if ( ss == 'H' ) : return 0 if ( ss == 'E' ) : return 1 if ( ss == 'C' ) : return 2 assert 0
secondary structure symbol to index .