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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(file_name):
 """Read configuration."""


    config = {}
    for name in (['.pyspelling.yml', '.spelling.yml'] if not file_name else [file_name]):
        if os.path.exists(name):
            if not file_name and name == '.spelling.yml':
                warn_deprecated(
                    "Using '.spelling.yml' as the default is deprecated. Default config is now '.pyspelling.yml'"
                )
            with codecs.open(name, 'r', encoding='utf-8') as f:
                config = yaml_load(f.read())
            break
    return config