code: def random(self: 'ErrorValue') -> np.ndarray:
          
          if isinstance(self.val, np.ndarray):
              # IGNORE:E1103
              return np.random.randn(self.val.shape) * self.err + self.val
          else:
              return np.random.randn() * self.err + self.val
docs: Sample a random number (array) of the distribution defined by
          mean=`self.val` and variance=`self.err`^2.