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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 random_string(**kwargs):
 """ By default generates a random string of 10 chars composed of digits and ascii lowercase letters. String length and pool can be override by using kwargs. Pool must be a list of strings """

    n = kwargs.get('length', 10)
    pool = kwargs.get('pool') or string.digits + string.ascii_lowercase
    return ''.join(random.SystemRandom().choice(pool) for _ in range(n))