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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_entry(key):
 """ Get a configuration entry :param key: key name :returns: mixed value :raises KeyError: if key has not been found :raises TypeError: if key is not str """

    if type(key) != str:
        raise TypeError("key must be str")
    if key not in _config:
        raise KeyError("Nonexistent entry '{key}'".format(key=key))
    return _config[key]