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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def send_stream(stream, filename, size, mtime, mimetype=None, restricted=True, as_attachment=False, etag=None, content_md5=None, chunk_size=None, conditional=True, trusted=False):
 """Send the contents of a file to the client. .. warning:: It is very easy to be exposed to Cross-Site Scripting (XSS) attacks if you serve user uploaded files. Here are some recommendations: 1. Serve user uploaded files from a separate domain (not a subdomain). This way a malicious file can only attack other user uploaded files. 2. Prevent the browser from rendering and executing HTML files (by setting ``trusted=False``). 3. Force the browser to download the file as an attachment (``as_attachment=True``). :param stream: The file stream to send. :param filename: The file name. :param size: The file size. :param mtime: A Unix timestamp that represents last modified time (UTC). :param mimetype: The file mimetype. If ``None``, the module will try to guess. (Default: ``None``) :param restricted: If the file is not restricted, the module will set the cache-control. (Default: ``True``) :param as_attachment: If the file is an attachment. (Default: ``False``) :param etag: If defined, it will be set as HTTP E-Tag. :param content_md5: If defined, a HTTP Content-MD5 header will be set. :param chunk_size: The chunk size. :param conditional: Make the response conditional to the request. (Default: ``True``) :param trusted: Do not enable this option unless you know what you are doing. By default this function will send HTTP headers and MIME types that prevents your browser from rendering e.g. a HTML file which could contain a malicious script tag. (Default: ``False``) :returns: A Flask response instance. """

    chunk_size = chunk_size_or_default(chunk_size)

    # Guess mimetype from filename if not provided.
    if mimetype is None and filename:
        mimetype = mimetypes.guess_type(filename)[0]
    if mimetype is None:
        mimetype = 'application/octet-stream'

    # Construct headers
    headers = Headers()
    headers['Content-Length'] = size
    if content_md5:
        headers['Content-MD5'] = content_md5

    if not trusted:
        # Sanitize MIME type
        mimetype = sanitize_mimetype(mimetype, filename=filename)
        # See https://www.owasp.org/index.php/OWASP_Secure_Headers_Project
        # Prevent JavaScript execution
        headers['Content-Security-Policy'] = "default-src 'none';"
        # Prevent MIME type sniffing for browser.
        headers['X-Content-Type-Options'] = 'nosniff'
        # Prevent opening of downloaded file by IE
        headers['X-Download-Options'] = 'noopen'
        # Prevent cross domain requests from Flash/Acrobat.
        headers['X-Permitted-Cross-Domain-Policies'] = 'none'
        # Prevent files from being embedded in frame, iframe and object tags.
        headers['X-Frame-Options'] = 'deny'
        # Enable XSS protection (IE, Chrome, Safari)
        headers['X-XSS-Protection'] = '1; mode=block'

    # Force Content-Disposition for application/octet-stream to prevent
    # Content-Type sniffing.
    if as_attachment or mimetype == 'application/octet-stream':
        # See https://github.com/pallets/flask/commit/0049922f2e690a6d
        try:
            filenames = {'filename': filename.encode('latin-1')}
        except UnicodeEncodeError:
            filenames = {'filename*': "UTF-8''%s" % url_quote(filename)}
            encoded_filename = (unicodedata.normalize('NFKD', filename)
                                .encode('latin-1', 'ignore'))
            if encoded_filename:
                filenames['filename'] = encoded_filename
        headers.add('Content-Disposition', 'attachment', **filenames)
    else:
        headers.add('Content-Disposition', 'inline')

    # Construct response object.
    rv = current_app.response_class(
        FileWrapper(stream, buffer_size=chunk_size),
        mimetype=mimetype,
        headers=headers,
        direct_passthrough=True,
    )

    # Set etag if defined
    if etag:
        rv.set_etag(etag)

    # Set last modified time
    if mtime is not None:
        rv.last_modified = int(mtime)

    # Set cache-control
    if not restricted:
        rv.cache_control.public = True
        cache_timeout = current_app.get_send_file_max_age(filename)
        if cache_timeout is not None:
            rv.cache_control.max_age = cache_timeout
            rv.expires = int(time() + cache_timeout)

    if conditional:
        rv = rv.make_conditional(request)

    return rv