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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 RetrievePluginAsset(self, run, plugin_name, asset_name):
 """Return the contents for a specific plugin asset from a run. Args: run: The string name of the run. plugin_name: The string name of a plugin. asset_name: The string name of an asset. Returns: The string contents of the plugin asset. Raises: KeyError: If the asset is not available. """

    accumulator = self.GetAccumulator(run)
    return accumulator.RetrievePluginAsset(plugin_name, asset_name)