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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 pgettext(msgctxt, message):
 """'Particular gettext' function. It works with 'msgctxt' .po modifiers and allow duplicate keys with different translations. Python 2 don't have support for this GNU gettext function, so we reimplement it. It works by joining msgctx and msgid by '4' byte."""

    key = msgctxt + '\x04' + message
    translation = get_translation().gettext(key)
    return message if translation == key else translation