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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 generate_name(length=15, not_in=None):
 """ Generates a random string of lowercase letters with the given length. Parameters: length (int):
 Length of the string to output. not_in (list):
 Only return a string not in the given iterator. Returns: str: A new name thats not in the given list. """

    value = ''.join(random.choice(string.ascii_lowercase) for i in range(length))

    while (not_in is not None) and (value in not_in):
        value = ''.join(random.choice(string.ascii_lowercase) for i in range(length))

    return value