def find_paren_match(test_str):
    """Find matching closing parenthesis by searching forward,
    returns -1 if no match is found"""
    paren_count = 1
    ind = -1
    for (i, char) in enumerate(test_str):
        if char == '(':
            paren_count += 1
        elif char == ')':
            paren_count -= 1
        if paren_count == 0:
            return i
    return ind