[py3] Prepared MySQL backend for Python 3 compatibility

try:

    from itertools import zip_longest

except ImportError:

    from itertools import izip_longest as zip_longest

from django.db.models.sql import compiler

class SQLCompiler(compiler.SQLCompiler):

    def resolve_columns(self, row, fields=()):

        values = []

        index_extra_select = len(self.query.extra_select)

        for value, field in map(None, row[index_extra_select:], fields):

        for value, field in zip_longest(row[index_extra_select:], fields):

            if (field and field.get_internal_type() in ("BooleanField", "NullBooleanField") and

                value in (0, 1)):

                value = bool(value)

import re

from .base import FIELD_TYPE

from django.db.backends import BaseDatabaseIntrospection

from django.utils import six

from MySQLdb import ProgrammingError, OperationalError

from MySQLdb.constants import FIELD_TYPE

import re

foreign_key_re = re.compile(r"\sCONSTRAINT `[^`]*` FOREIGN KEY \(`([^`]*)`\) REFERENCES `([^`]*)` \(`([^`]*)`\)")