def str_find_between_tags(string, start='', end='', case=True):
    """ Returns a substring between two string tags """
    if not case:
        string_orig = string
        string = string.lower()
        start = start.lower()
        end = end.lower()
    if start:
        s = string.find(start)
    else:
        s = 0
    if end:
        e = string.find(end, s + len(start))
    else:
        e = len(string)
    if s < 0 or e < 0:
        return ''
    if not case:
        return string_orig[s + len(start):e]
    return string[s + len(start):e]
