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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(self, key, value):
 """Set a value in the `Bison` configuration. Args: key (str):
 The configuration key to set a new value for. value: The value to set. """

        # the configuration changes, so we invalidate the cached config
        self._full_config = None
        self._override[key] = value