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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 _config_data_files(base_dirs, extensions=(".cfg", )):
 """Find all subdirectory configuration files. Searches each base directory relative to this setup.py file and finds all files ending in the extensions provided. :param base_dirs: iterable of relative base directories to search :param extensions: iterable of file extensions to include (with '.' prefix) :returns: list of 2-element tuples compatible with `setuptools.setup` """

    data_files = []
    pkg_root = os.path.realpath(os.path.dirname(__file__)) + "/"
    for base_dir in base_dirs:
        new_data_files = []
        for ext in extensions:
            configs = glob(os.path.join(pkg_root, base_dir, "*" + ext))
            configs = [c.replace(pkg_root, "") for c in configs]
            new_data_files.extend(configs)
        data_files.append((base_dir, new_data_files))

    return data_files