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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 is_file_url(url):
 """Returns true if the given url is a file url"""

    from .misc import to_text

    if not url:
        return False
    if not isinstance(url, six.string_types):
        try:
            url = getattr(url, "url")
        except AttributeError:
            raise ValueError("Cannot parse url from unknown type: {0!r}".format(url))
    url = to_text(url, encoding="utf-8")
    return urllib_parse.urlparse(url.lower()).scheme == "file"