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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 enumerate_otus(fasta_filepath, output_filepath=None, label_prefix="", label_suffix="", retain_label_as_comment=False, count_start=0):
 """ Writes unique, sequential count to OTUs fasta_filepath = input fasta filepath output_filepath = output fasta filepath label_prefix = string to place before enumeration label_suffix = string to place after enumeration retain_label_as_comment = if True, will place existing label in sequence comment, after a tab count_start = number to start enumerating OTUs with """


    fasta_i = open(fasta_filepath, "U")

    if not output_filepath:
        _, output_filepath = mkstemp(prefix='enumerated_seqs_',
                                     suffix='.fasta')

    fasta_o = open(output_filepath, "w")

    for label, seq in parse_fasta(fasta_i):
        curr_label = ">" + label_prefix + str(count_start) + label_suffix
        if retain_label_as_comment:
            curr_label += '\t' + label
        fasta_o.write(curr_label.strip() + '\n')
        fasta_o.write(seq.strip() + '\n')
        count_start += 1

    return output_filepath