libcst_parse_and_transform_function_name_with_cst_transformer.py

1import libcst as cst
2
3class MyTransformer(cst.CSTTransformer):
4    def leave_FunctionDef(
5        self, original_node: cst.FunctionDef, updated_node: cst.FunctionDef
6    ) -> cst.FunctionDef:
7        # Rename all functions to "denied"
8        return updated_node.with_changes(name=cst.Name("denied"))
9
10source_code = """
11def hello():
12    print("Hello, world!")
13"""
14
15# Parse the code into a CST
16source_tree = cst.parse_module(source_code)
17
18# Transform the tree
19transformer = MyTransformer()
20modified_tree = source_tree.visit(transformer)
21
22# Print the resulting code
23print(modified_tree.code)