code: def canonicalize_header(key):
      
      bits = key.split('-')
      for idx, b in enumerate(bits):
          bits[idx] = b.capitalize()
      return '-'.join(bits)
docs: Returns the canonicalized header name for the header name provided as an argument.
      The canonicalized header name according to the HTTP RFC is Kebab-Camel-Case.
  
      Keyword arguments:
      key -- the name of the header