parameters: (self, dir)
docstring: Create this directory if it does not exist, and change into it
docstring_summary: Create this directory if it does not exist, and change into it
docstring_tokens: Create this directory if it does not exist and change into it
function: def workdir(self, dir):
          "Create this directory if it does not exist, and change into it"
          raise NotImplementedError
function_tokens: def workdir ( self , dir ) : raise NotImplementedError