<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def is_gzipfile(filename):
 """ Attempt to ascertain the gzip status of a file based on the "magic signatures" of the file. This was taken from the stack overflow post http://stackoverflow.com/questions/13044562/python-mechanism-to-identify-compressed-file-type\ -and-uncompress :param str filename: A path to a file :return: True if the file appears to be gzipped else false :rtype: bool """

    assert os.path.exists(filename), 'Input {} does not '.format(filename) + \
        'point to a file.'
    with open(filename, 'rb') as in_f:
        start_of_file = in_f.read(3)
        if start_of_file == '\x1f\x8b\x08':
            return True
        else:
            return False