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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 _set_opt(config_dict, path, value):
 """Set the value in the dictionary at the given path if the value is not None."""

    if value is None:
        return

    if '.' not in path:
        config_dict[path] = value
        return

    key, rest = path.split(".", 1)
    if key not in config_dict:
        config_dict[key] = {}

    _set_opt(config_dict[key], rest, value)