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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(self, key, default=_NoValue):
 """Returns the value of Spark runtime configuration property for the given key, assuming it is set. """

        self._checkType(key, "key")
        if default is _NoValue:
            return self._jconf.get(key)
        else:
            if default is not None:
                self._checkType(default, "default")
            return self._jconf.get(key, default)