How to use the tomlkit._compat.decode function in tomlkit

def _render_simple_item(self, key, item, prefix=None):
        if key is None:
            return item.as_string()

        _key = key.as_string()
        if prefix is not None:
            _key = prefix + "." + _key

        return "{}{}{}{}{}{}{}".format(
            item.trivia.indent,
            decode(_key),
            key.sep,
            decode(item.as_string()),
            item.trivia.comment_ws,
            decode(item.trivia.comment),
            item.trivia.trail,
        )

def _render_simple_item(self, key, item, prefix=None):
        if key is None:
            return item.as_string()

        _key = key.as_string()
        if prefix is not None:
            _key = prefix + "." + _key

        return "{}{}{}{}{}{}{}".format(
            item.trivia.indent,
            decode(_key),
            key.sep,
            decode(item.as_string()),
            item.trivia.comment_ws,
            decode(item.trivia.comment),
            item.trivia.trail,
        )

def as_string(self):  # type: () -> str
        return "{}{}{}".format(
            self._trivia.indent, decode(self._trivia.comment), self._trivia.trail
        )

def _render_simple_item(self, key, item, prefix=None):
        if key is None:
            return item.as_string()

        _key = key.as_string()
        if prefix is not None:
            _key = prefix + "." + _key

        return "{}{}{}{}{}{}{}".format(
            item.trivia.indent,
            decode(_key),
            key.sep,
            decode(item.as_string()),
            item.trivia.comment_ws,
            decode(item.trivia.comment),
            item.trivia.trail,
        )

def escape_string(s):
    s = decode(s)

    res = []
    start = 0

    def flush():
        if start != i:
            res.append(s[start:i])

        return i + 1

    i = 0
    while i < len(s):
        c = s[i]
        if c in '"\\\n\r\t\b\f':
            start = flush()
            res.append("\\" + _escapes[c])

def __str__(self):  # type: () -> str
        return "{}{}".format(self._trivia.indent, decode(self._trivia.comment))

def _render_aot_table(self, table, prefix=None):  # (Table, Optional[str]) -> str
        cur = ""

        _key = prefix or ""

        if not table.is_super_table():
            open_, close = "[[", "]]"

            cur += "{}{}{}{}{}{}{}".format(
                table.trivia.indent,
                open_,
                decode(_key),
                close,
                table.trivia.comment_ws,
                decode(table.trivia.comment),
                table.trivia.trail,
            )

        for k, v in table.value.body:
            if isinstance(v, Table):
                if v.is_super_table():
                    if k.is_dotted():
                        # Dotted key inside table
                        cur += self._render_table(k, v)
                    else:
                        cur += self._render_table(k, v, prefix=_key)
                else:
                    cur += self._render_table(k, v, prefix=_key)
            elif isinstance(v, AoT):
                cur += self._render_aot(k, v, prefix=_key)
            else: