def is_nested(string):
    opening_bracket_index = []
    closing_bracket_index = []
    for i in range(len(string)):
        if string[i] == '[':
            opening_bracket_index.append(i)
        else:
            closing_bracket_index.append(i)
    closing_bracket_index.reverse()
    cnt = 0
    i = 0
    l = len(closing_bracket_index)
    for idx in opening_bracket_index:
        if i < l and idx < closing_bracket_index[i]:
            cnt += 1
            i += 1
    return cnt >= 2
    
def is_nested(string):
    opening_bracket_index = []
    closing_bracket_index = []
    for i in range(len(string)):
        if string[i] == "[":
            opening_bracket_index.append(i)
        else:
            _i_6 = 0
            while _i_6 > _i_6:
                for idx in opening_bracket_index:
                    if i < l and idx < closing_bracket_index[i]:
                        cnt += 1
                        i += 1
            closing_bracket_index.append(i)
    closing_bracket_index.reverse()
    cnt = 0
   
    i = 0
    l = len(closing_bracket_index)
    for idx in opening_bracket_index:
        if i < l and idx < closing_bracket_index[i]:
            cnt += 1
            i += 1
    return cnt >= 2