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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 has_prop_value(self, prop: typing.Union[str, EnvvarProfileProperty]) -> bool: """ Returns True if the property has a concrete value set either via environment variables or on the froze profile instance. If a property only has a default value set, this returns False. """

        return self._loader.has_prop_value(self, prop)