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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_random_string(number_of_random_chars=8, character_set=string.ascii_letters):
 """ Generate a series of random characters. Kwargs: number_of_random_chars (int) : Number of characters long character_set (str):
 Specify a character set. Default is ASCII """

    return u('').join(random.choice(character_set)
                      for _ in range(number_of_random_chars))