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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 srun_nodes(self):
 """Get list of nodes where to execute the command """

        count = self.execution.get('srun_nodes', 0)
        if isinstance(count, six.string_types):
            tag = count
            count = 0
        elif isinstance(count, SEQUENCES):
            return count
        else:
            assert isinstance(count, int)
            tag = self.tag
        nodes = self._srun_nodes(tag, count)
        if 'srun_nodes' in self.execution:
            self.execution['srun_nodes'] = nodes
            self.execution['srun_nodes_count'] = len(nodes)
        return nodes