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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 get_module_functions(modules):
 """Finds functions that do not have implemented derivatives. Args: modules: A list of Python modules. Functions contained in these modules will be checked for membership in 'implemented', and if not found, will be added to an 'unimplemented' set implemented: A Python object containing implemented derivatives. A function should be checkable for membership using the `fn in implemented` syntax. Returns: module_fns: A set of functions, builtins or ufuncs in `modules`. """

  module_fns = set()
  for module in modules:
    for key in dir(module):
      attr = getattr(module, key)
      if isinstance(
          attr, (types.BuiltinFunctionType, types.FunctionType, numpy.ufunc)):
        module_fns.add(attr)
  return module_fns