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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 get_random(self, n, l=None):
 """ Return n random sequences from this Fasta object """

        random_f = Fasta()
        if l:
            ids = self.ids[:]
            random.shuffle(ids)
            i = 0
            while (i < n) and (len(ids) > 0):
                seq_id = ids.pop()
                if (len(self[seq_id]) >= l):
                    start = random.randint(0, len(self[seq_id]) - l)
                    random_f["random%s" % (i + 1)] = self[seq_id][start:start+l]
                    i += 1
            if len(random_f) != n:
                sys.stderr.write("Not enough sequences of required length")
                return
            else:
                return random_f

        else:
            choice = random.sample(self.ids, n)
            for i in range(n):
                random_f[choice[i]] = self[choice[i]]
        return random_f