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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 walk_nodes(self, node, original):
 """ Iterate over the nodes recursively yielding the templatetag 'sass_src' """

        try:
            # try with django-compressor<2.1
            nodelist = self.parser.get_nodelist(node, original=original)
        except TypeError:
            nodelist = self.parser.get_nodelist(node, original=original, context=None)
        for node in nodelist:
            if isinstance(node, SassSrcNode):
                if node.is_sass:
                    yield node
            else:
                for node in self.walk_nodes(node, original=original):
                    yield node