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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_descriptions(fastas):
 """ get the description for each ORF """

    id2desc = {}
    for fasta in fastas:
        for seq in parse_fasta(fasta):
            header = seq[0].split('>')[1].split(' ')
            id = header[0]
            if len(header) > 1:
                desc = ' '.join(header[1:])
            else:
                desc = 'n/a'
            length = float(len([i for i in seq[1].strip() if i != '*']))
            id2desc[id] = [fasta, desc, length]
    return id2desc