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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 _get_encoding_opt(synchronizer, extra_opts, default):
 """Helper to figure out encoding setting inside constructors."""

    encoding = default
    # if synchronizer and "encoding" in synchronizer.options:
    #     encoding = synchronizer.options.get("encoding")
    if extra_opts and "encoding" in extra_opts:
        encoding = extra_opts.get("encoding")
    if encoding:
        # Normalize name (e.g. 'UTF8' => 'utf-8')
        encoding = codecs.lookup(encoding).name
    # print("_get_encoding_opt", encoding)
    return encoding or None