Return an iterable of (tokentype, value) pairs generated from
        `text`. If `unfiltered` is set to `True`, the filtering mechanism
        is bypassed even if filters are defined.

        Also preprocess the text, i.e. expand tabs and strip it if
        wanted and applies registered filters.

        Split ``text`` into (tokentype, text) pairs.

        ``stack`` is the initial stack (default: ``['root']``)

def get_tokens(text, encoding=None):
        """
        Return an iterable of (tokentype, value) pairs generated from
        `text`. If `unfiltered` is set to `True`, the filtering mechanism
        is bypassed even if filters are defined.

        Also preprocess the text, i.e. expand tabs and strip it if
        wanted and applies registered filters.

        Split ``text`` into (tokentype, text) pairs.

        ``stack`` is the initial stack (default: ``['root']``)
        """
        if isinstance(text, file_types):
            text = text.read()

        if isinstance(text, text_type):
            pass
        elif isinstance(text, bytes):
            if encoding:
                text = text.decode(encoding)
            else:
                try:
                    text = text.decode('utf-8')
                except UnicodeDecodeError:
                    text = text.decode('unicode-escape')
        else:
            raise TypeError(u"Expected text or file-like object, got {!r}".
                            format(type(text)))

        iterable = enumerate(text)
        for pos, char in iterable:
            for rexmatch, action in SQL_REGEX:
                m = rexmatch(text, pos)

                if not m:
                    continue
                elif isinstance(action, tokens._TokenType):
                    yield action, m.group()
                elif callable(action):
                    yield action(m.group())

                consume(iterable, m.end() - pos - 1)
                break
            else:
                yield tokens.Error, char