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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 prepare_include(ctx, include, output):
 """Process and filter include file to produce list of names for dictionary."""

    click.echo('chemdataextractor.dict.prepare_include')
    for i, line in enumerate(include):
        print('IN%s' % i)
        for tokens in _make_tokens(line.strip()):
            output.write(u' '.join(tokens))
            output.write(u'\n')