code: def umask(self, use_sudo=False):
          
          func = use_sudo and run_as_root or self.run
          return func('umask')
docs: Get the user's umask.
  
          Returns a string such as ``'0002'``, representing the user's umask
          as an octal number.
  
          If `use_sudo` is `True`, this function returns root's umask.