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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 identify_gwf(origin, filepath, fileobj, *args, **kwargs):
 """Identify a filename or file object as GWF This function is overloaded in that it will also identify a cache file as 'gwf' if the first entry in the cache contains a GWF file extension """

    # pylint: disable=unused-argument

    # try and read file descriptor
    if fileobj is not None:
        loc = fileobj.tell()
        fileobj.seek(0)
        try:
            if fileobj.read(4) == GWF_SIGNATURE:
                return True
        finally:
            fileobj.seek(loc)
    if filepath is not None:
        if filepath.endswith('.gwf'):
            return True
        if filepath.endswith(('.lcf', '.cache')):
            try:
                cache = read_cache(filepath)
            except IOError:
                return False
            else:
                if cache[0].path.endswith('.gwf'):
                    return True