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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_dna(n):
    '''Generate a random DNA sequence.

    :param n: Output sequence length.
    :type n: int
    :returns: Random DNA sequence of length n.
    :rtype: coral.DNA

    '''
    return coral.DNA(''.join([random.choice('ATGC') for i in range(n)]))