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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 combined_download(accounts, days=60):
 """Download OFX files and combine them into one It expects an 'accounts' list of ofxclient.Account objects as well as an optional 'days' specifier which defaults to 60 """


    client = Client(institution=None)

    out_file = StringIO()
    out_file.write(client.header())
    out_file.write('<OFX>')
    for a in accounts:
        ofx = a.download(days=days).read()
        stripped = ofx.partition('<OFX>')[2].partition('</OFX>')[0]
        out_file.write(stripped)

    out_file.write("</OFX>")
    out_file.seek(0)

    return out_file