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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 merge_config_files(fnames):
 """Merge configuration files, preferring definitions in latter files. """

    def _load_yaml(fname):
        with open(fname) as in_handle:
            config = yaml.safe_load(in_handle)
        return config
    out = _load_yaml(fnames[0])
    for fname in fnames[1:]:
        cur = _load_yaml(fname)
        for k, v in cur.items():
            if k in out and isinstance(out[k], dict):
                out[k].update(v)
            else:
                out[k] = v
    return out