def _parse_section(token_iter):
    '''take a stream of tokens, and create the tree structure that is defined
    by the s-expressions
    '''
    sexp = []
    for token in token_iter:
        if token == '(':
            new_sexp = _parse_section(token_iter)
            if not _match_section(new_sexp, UNWANTED_SECTIONS):
                sexp.append(new_sexp)
        elif token == ')':
            return sexp
        else:
            sexp.append(token)
    return sexp
def _parse_section ( token_iter ) : sexp = [ ] for token in token_iter : if token == '(' : new_sexp = _parse_section ( token_iter ) if not _match_section ( new_sexp , UNWANTED_SECTIONS ) : sexp . append ( new_sexp ) elif token == ')' : return sexp else : sexp . append ( token ) return sexp
take a stream of tokens, and create the tree structure that is defined
    by the s-expressions