(s, j, b, S_cosets)
return None
Return the representative h satisfying s[h[b]] == j

    If there is not such a representative return None
Return the representative h satisfying s[h[b]] == j
Return the representative h satisfying s [ h [ b ]] == j
def _trace_S(s, j, b, S_cosets):
    """
    Return the representative h satisfying s[h[b]] == j

    If there is not such a representative return None
    """
    for h in S_cosets[b]:
        if s[h[b]] == j:
            return h
    return None
def _trace_S ( s , j , b , S_cosets ) : for h in S_cosets [ b ] : if s [ h [ b ] ] == j : return h return None