json parser

shit_json.py

def parse(data):
    char = data.pop(0)
    if char == '[':
        return parse_list(data)
    elif char == '{':
        return parse_object(data)
    elif '0' <= char <= '9':
        return parse_int(char, data)
    elif char in 'tfn':
        return parse_atom(data)
    elif char == '"':
        return parse_string(data)
    else:
        lol_parser_error()

def parse_atom(data):
    part = data.pop(0) + data.pop(0) + data.pop(0)
    if part == 'ull':
        return None
    if part == 'rue':
        return True
    if part == 'als':
        data.pop(0)
        return False
    parser_error()

def parse_list(data):
    out = []
    while True:
        out.append(parse(data))
        char = data.pop(0)
        if char == ']':
            return out
        else:
            assert char == ','

def parse_object(data):
    out = {}
    while True:
        key = parse(data)
        assert data.pop(0) == ':'
        out[key] = parse(data)
        char = data.pop(0)
        if char == '}':
            return out
        else:
            assert char == ','

def parse_string(data):
    out = []
    while True:
        char = data.pop(0)
        if char == '"':
            return ''.join(out)
        elif char == '\\':
            out.append(data.pop(0))
        else:
            out.append(char)

def parse_int(value, data):
    while '0' <= data[0] <= '9':
        value += data.pop(0)
    return int(value)

json = '[1,null,2,[1,2,{"gg\\"":2,3:400,true:false}]]'

print parse(list(json))