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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 find_data(path, warn=True):
 """Return the absolute path to a data file within the data directory."""

    full_path = os.path.join(get_data_dir(), path)
    if warn and not os.path.isfile(full_path):
        for package in PACKAGES:
            if path == package.path:
                log.warn('%s doesn\'t exist. Run `cde data download` to get it.' % path)
                break
    return full_path