code: def remove_by_hash(hashval: str):
      
      key_details = get_keys()
      with authorized_keys('w') as ak:
          for keyhash, key in key_details:
              if keyhash != hashval:
                  ak.write(f'{key}\n')
                  break
          else:
              raise KeyError(hashval)
docs: Remove the key whose md5 sum matches hashval.
  
      :raises: KeyError if the hashval wasn't found