def secure_filename(filename):
    r"""Borrowed from :mod:`werkzeug.utils`, under the BSD 3-clause license.

    Pass it a filename and it will return a secure version of it.  This
    filename can then safely be stored on a regular file system and passed
    to :func:`os.path.join`.  The filename returned is an ASCII only string
    for maximum portability.

    On windows systems the function also makes sure that the file is not
    named after one of the special device files.

    >>> secure_filename("My cool movie.mov")
    'My_cool_movie.mov'
    >>> secure_filename("../../../etc/passwd")
    'etc_passwd'
    >>> secure_filename(u'i contain cool \xfcml\xe4uts.txt')
    'i_contain_cool_umlauts.txt'

    The function might return an empty filename.  It's your responsibility
    to ensure that the filename is unique and that you generate random
    filename if the function returned an empty one.

    :param filename: the filename to secure
    """
    _filename_ascii_strip_re = re.compile(r'[^A-Za-z0-9_.-]')
    _windows_device_files = ('CON', 'AUX', 'COM1', 'COM2', 'COM3', 'COM4',
                             'LPT1', 'LPT2', 'LPT3', 'PRN', 'NUL')
    if isinstance(filename, text_type):
        from unicodedata import normalize
        filename = normalize('NFKD', filename).encode('ascii', 'ignore')
        if not PY2:
            filename = filename.decode('ascii')
    for sep in os.path.sep, os.path.altsep:
        if sep:
            filename = filename.replace(sep, ' ')
    filename = str(_filename_ascii_strip_re.sub('', '_'.join(
                   filename.split()))).strip('._')

    # on nt a couple of special files are present in each folder.  We
    # have to ensure that the target file is not such a filename.  In
    # this case we prepend an underline
    if os.name == 'nt' and filename and \
       filename.split('.')[0].upper() in _windows_device_files:
        filename = '_' + filename

    return filename
def _send_request(
        self,
        request: HttpRequest,
        **kwargs: Any
    ) -> Awaitable[AsyncHttpResponse]:
        """Runs the network request through the client's chained policies.

        >>> from azure.core.rest import HttpRequest
        >>> request = HttpRequest("GET", "https://www.example.org/")
        <HttpRequest [GET], url: 'https://www.example.org/'>
        >>> response = await client._send_request(request)
        <AsyncHttpResponse: 200 OK>

        For more information on this code flow, see https://aka.ms/azsdk/python/protocol/quickstart

        :param request: The network request you want to make. Required.
        :type request: ~azure.core.rest.HttpRequest
        :keyword bool stream: Whether the response payload will be streamed. Defaults to False.
        :return: The response of your network call. Does not do error handling on your response.
        :rtype: ~azure.core.rest.AsyncHttpResponse
        """

        request_copy = deepcopy(request)
        request_copy.url = self._client.format_url(request_copy.url)
        return self._client.send_request(request_copy, **kwargs)