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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 PluginAssets(self, plugin_name):
 """Get index of runs and assets for a given plugin. Args: plugin_name: Name of the plugin we are checking for. Returns: A dictionary that maps from run_name to a list of plugin assets for that run. """

    with self._accumulators_mutex:
      # To avoid nested locks, we construct a copy of the run-accumulator map
      items = list(six.iteritems(self._accumulators))

    return {run: accum.PluginAssets(plugin_name) for run, accum in items}