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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 read_config_files(files):
 """Read and merge a list of config files."""


    config = ConfigObj()

    for _file in files:
        _config = read_config_file(_file)
        if bool(_config) is True:
            config.merge(_config)
            config.filename = _config.filename

    return config