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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 train_all(ctx, output):
 """Train POS tagger on WSJ, GENIA, and both. With and without cluster features."""

    click.echo('chemdataextractor.pos.train_all')
    click.echo('Output: %s' % output)
    ctx.invoke(train, output='%s_wsj_nocluster.pickle' % output, corpus='wsj', clusters=False)
    ctx.invoke(train, output='%s_wsj.pickle' % output, corpus='wsj', clusters=True)
    ctx.invoke(train, output='%s_genia_nocluster.pickle' % output, corpus='genia', clusters=False)
    ctx.invoke(train, output='%s_genia.pickle' % output, corpus='genia', clusters=True)
    ctx.invoke(train, output='%s_wsj_genia_nocluster.pickle' % output, corpus='wsj+genia', clusters=False)
    ctx.invoke(train, output='%s_wsj_genia.pickle' % output, corpus='wsj+genia', clusters=True)