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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 _msgmerge(po_path, pot_file, backup):
 """Merge an existing .po file with new translations. :arg po_path: path to the .po file :arg pot_file: a file-like object for the related templates :arg backup: whether or not to create backup .po files """

    pot_file.seek(0)
    command = [
        'msgmerge',
        '--update',
        '--width=200',
        '--backup=%s' % ('simple' if backup else 'off'),
        po_path,
        '-'
    ]
    p3 = Popen(command, stdin=pot_file)
    p3.communicate()