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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 check_hardware_virtualization(self, source_node):
 """ Checks if hardware virtualization can be used. :returns: boolean """


        for project in self._projects.values():
            for node in project.nodes:
                if node == source_node:
                    continue
                if node.hw_virtualization and node.__class__.__name__ != source_node.__class__.__name__:
                    return False
        return True