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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 visit_Module(self, node):
 """Add itertools import for imap, izip or ifilter iterator."""

        self.generic_visit(node)
        import_alias = ast.alias(name='itertools', asname=mangle('itertools'))
        if self.use_itertools:
            importIt = ast.Import(names=[import_alias])
            node.body.insert(0, importIt)
        return node