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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 update(database, table, key):
 """Does a single update operation."""

    field = random.randrange(10)
    value = ''.join(random.choice(string.printable) for i in range(100))
    with database.batch() as batch:
        batch.update(table=table, columns=('id', 'field%d' % field),
                     values=[(key, value)])