Cleanup of URL check and fitting changes into normal b5 coding style

class Skeleton:

    NON_URL_SKELETON = re.compile('^[A-Za-z0-9_-]+$')

    def __init__(self, skeleton):

        self._skeleton = skeleton

    def __init__(self, skeleton_identified):

        self._skeleton_identified = skeleton_identified

    def get_url(self):

        if not self._url:

            non_url_skeleton = re.compile('^[A-Za-z0-9_-]+$')

            if non_url_skeleton.match(self._skeleton):

                self._url = 'https://git.team23.de/build/b5-skel-{skeleton}.git'.format(skeleton=self._skeleton)

                '''if it's not a public repository, clone using ssh in order to allow ssh key file auth'''

                if not self.__is_public_repository(self._url):

                    self._url = 'git@git.team23.de:build/b5-skel-{skeleton}.git'.format(skeleton=self._skeleton)

            else:

                self._url = self._skeleton

        try:

            return self._url

        except AttributeError:

            skeleton_url = self._skeleton_identified

            if self.NON_URL_SKELETON.match(skeleton_url):

                skeleton_url = 'https://git.team23.de/build/b5-skel-{skeleton}.git'.format(skeleton=self._skeleton_identified)

                # If it's not a public repository, clone using ssh in order to allow ssh key file auth

                if not self.__is_public_repository(skeleton_url):

                    skeleton_url = 'git@git.team23.de:build/b5-skel-{skeleton}.git'.format(skeleton=self._skeleton_identified)

            self._url = skeleton_url

            return self._url

    def __is_public_repository(self, url):

        request = urllib.request.urlopen(self._url)

        request = urllib.request.urlopen(url)

        request_url = request.geturl()

        if self._url == request_url or os.path.splitext(self._url)[0] == request_url:

        if url == request_url or url.rsplit('.', 1)[0] == request_url:

            try:

                if request.getcode() == 200:

                    return True