code: def spread(iterable):
      
      if len(iterable) == 1:
          return 0
  
      iterable = iterable.copy()
      iterable.sort()
  
      max_diff = max(abs(i - j) for (i, j) in zip(iterable[1:], iterable[:-1]))
  
      return max_diff
docs: Returns the maximal spread of a sorted list of numbers.
  
      Parameters
      ----------
      iterable
          A list of numbers.
  
      Returns
      -------
      max_diff
          The maximal difference when the iterable is sorted.
  
  
      Examples
      -------
      >>> spread([1, 11, 13, 15])
      10
      
      >>> spread([1, 15, 11, 13])
      10