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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 alignfast(names, seqs):
 """ Performs MUSCLE alignments on cluster and returns output as string """

    matfile = op.join(datadir, "blosum80.mat")
    cmd = "poa -read_fasta - -pir stdout {0} -tolower -silent -hb -fuse_all".format(matfile)
    p = Popen(cmd, shell=True, stdin=PIPE, stdout=PIPE, stderr=STDOUT, close_fds=True)
    s = ""
    for i, j in zip(names, seqs):
        s += "\n".join((i, j)) + "\n"
    return p.communicate(s)[0]