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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 entrez(db, acc):
 """ search entrez using specified database and accession """

    c1 = ['esearch', '-db', db, '-query', acc]
    c2 = ['efetch', '-db', 'BioSample', '-format', 'docsum']
    p1 = Popen(c1, stdout = PIPE, stderr = PIPE)
    p2 = Popen(c2, stdin = p1.stdout, stdout = PIPE, stderr = PIPE)
    return p2.communicate()