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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 init(**kwargs):
 """Initialize the specified names in the specified databases. The general process is as follows: - Ensure the database in question exists - Ensure all tables exist in the database. """


    # TODO: Iterate through all engines in name set.
    database = kwargs.pop('database', False)
    if database and not database_exists(engine['default'].url):
        create_database(engine['default'].url, encoding='utf8')
        clear_cache()

    expression = lambda target, table: table.create(target)
    test = lambda target, table: table.exists(target)
    op(expression, test=test, primary='init', secondary='create', **kwargs)