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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 _needle(fa, fb, needlefile, a, b, results):
 """ Run single needle job """

    from Bio.Emboss.Applications import NeedleCommandline

    needle_cline = NeedleCommandline(asequence=fa, bsequence=fb,
                        gapopen=10, gapextend=0.5, outfile=needlefile)
    stdout, stderr = needle_cline()
    nh = NeedleHeader(needlefile)
    FileShredder([fa, fb, needlefile], verbose=False)
    r = ["\t".join((a, b, nh.identity, nh.score))]

    results.extend(r)