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Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def delete_database(client, db_name, username=None, password=None):
 """Delete Arangodb database """


    (username, password) = get_user_creds(username, password)

    sys_db = client.db("_system", username=username, password=password)

    try:
        return sys_db.delete_database(db_name)
    except Exception:
        log.warn("No arango database {db_name} to delete, does not exist")