def unquote_header_value(value, is_filename=False):
if value and value[<NUM_LIT:0>] == value[-<NUM_LIT:1>] == '<STR_LIT:">':<EOL><INDENT>value = value[<NUM_LIT:1>:-<NUM_LIT:1>]<EOL>if not is_filename or value[:<NUM_LIT:2>] != '<STR_LIT>':<EOL><INDENT>return value.replace('<STR_LIT>', '<STR_LIT:\\>').replace('<STR_LIT>', '<STR_LIT:">')<EOL><DEDENT><DEDENT>return value<EOL>
r"""Unquotes a header value.  (Reversal of :func:`quote_header_value`).
    This does not use the real unquoting but what browsers are actually
    using for quoting.

    :param value: the header value to unquote.