human
Complete the below
def groups():

    ''''Builder for rebulk object.
    :return: Created Rebulk object
    :rtype: Rebulk'
    '''
 ... Write me a the Python program you requested?
assistant
#Here is the Python program you requested.
    rebulk = Rebulk()
    rebulk.defaults(name='group', marker=True)
    starting = '([{'
    ending = ')]}'
    def mark_groups(input_string):
        '\n                                Functional    pattern    to    mark    groups    (...),    [...]    and    {...}.\n\n                                :param    input_string:\n                                :return:\n                                '
        openings = ([], [], [])
        i = 0
        ret = []
        for char in input_string:
            start_type = starting.find(char)
            if (start_type > (-1)):
                openings[start_type].append(i)
            i += 1
            end_type = ending.find(char)
            if (end_type > (-1)):
                try:
                    start_index = openings[end_type].pop()
                    ret.append((start_index, i))
                except IndexError:
                    pass
        return ret
    rebulk.functional(mark_groups)
    return rebulk