# -*- coding: utf-8 -*-
"""
    flask._compat
    ~~~~~~~~~~~~~

    Some py2/py3 compatibility support that is not yet available in
    "six" 1.3.0.
    There are bugs open for "six" for all this stuff, so we can remove it
    again from here as soon as we require a new enough "six" release.

    :copyright: (c) 2013 by Armin Ronacher.
    :license: BSD, see LICENSE for more details.
"""

# -*- coding: utf-8 -*-
"""
    flask._compat
    ~~~~~~~~~~~~~

    Some py2/py3 compatibility support based on a stripped down
    version of six so we don't have to depend on a specific version
    of it.

    :copyright: (c) 2013 by Armin Ronacher.
    :license: BSD, see LICENSE for more details.
"""
import sys

PY2 = sys.version_info[0] == 2
PYPY = hasattr(sys, 'pypy_translation_info')
_identity = lambda x: x


if not PY2:
    unichr = chr
    range_type = range
    text_type = str
    string_types = (str,)

    iterkeys = lambda d: iter(d.keys())
    itervalues = lambda d: iter(d.values())
    iteritems = lambda d: iter(d.items())

    import pickle
    from io import BytesIO, StringIO
    NativeStringIO = StringIO

    def reraise(tp, value, tb=None):
        if value.__traceback__ is not tb:
            raise value.with_traceback(tb)
        raise value

    ifilter = filter
    imap = map
    izip = zip
    intern = sys.intern

    implements_iterator = _identity
    implements_to_string = _identity
    encode_filename = _identity
    get_next = lambda x: x.__next__

else:
    unichr = unichr
    text_type = unicode
    range_type = xrange
    string_types = (str, unicode)

    iterkeys = lambda d: d.iterkeys()
    itervalues = lambda d: d.itervalues()
    iteritems = lambda d: d.iteritems()

    import cPickle as pickle
    from cStringIO import StringIO as BytesIO, StringIO
    NativeStringIO = BytesIO

    exec('def reraise(tp, value, tb=None):\n raise tp, value, tb')

    from itertools import imap, izip, ifilter
    intern = intern

    def implements_iterator(cls):
        cls.next = cls.__next__
        del cls.__next__
        return cls

    def implements_to_string(cls):
        cls.__unicode__ = cls.__str__
        cls.__str__ = lambda x: x.__unicode__().encode('utf-8')
        return cls

    get_next = lambda x: x.next

    def encode_filename(filename):
        if isinstance(filename, unicode):
            return filename.encode('utf-8')
        return filename


def with_metaclass(meta, *bases):
    # This requires a bit of explanation: the basic idea is to make a
    # dummy metaclass for one level of class instanciation that replaces
    # itself with the actual metaclass.  Because of internal type checks
    # we also need to make sure that we downgrade the custom metaclass
    # for one level to something closer to type (that's why __call__ and
    # __init__ comes back from type etc.).
    #
    # This has the advantage over six.with_metaclass in that it does not
    # introduce dummy classes into the final MRO.
    class metaclass(meta):
        __call__ = type.__call__
        __init__ = type.__init__
        def __new__(cls, name, this_bases, d):
            if this_bases is None:
                return type.__new__(cls, name, (), d)
            return meta(name, bases, d)
    return metaclass('temporary_class', None, {})


try:
    from urllib.parse import quote_from_bytes as url_quote
except ImportError:
    from urllib import quote as url_quote

copy _compat.py from flask in here (and adapt docstring)