text: import ast
  
  from typing import Union, Tuple
  
  from mr_proper.public_api import is_function_pure
  
  
  AnyFuncdef = Union[ast.FunctionDef, ast.AsyncFunctionDef]
  
  
  def check_purity_of_functions(func_def: AnyFuncdef) -> Tuple[int, int, str]:
      if 'pure' in func_def.name.split('_') and not is_function_pure(func_def):
          return (
              func_def.lineno,
              func_def.col_offset,
              f'CFQ003 Function "{func_def.name}" is not pure.',
          )
  