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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 make_digest_file(data_file, digest_file):
    '''Create a file containing the hex digest string of a data file.'''

    hexdigest = get_file_hexdigest(data_file)
    fd = open(digest_file, 'w')
    fd.write(hexdigest)
    fd.close()