old_contents: # -*- coding: utf-8 -*-
  """Python package to support the research during
  the annual Lehrexkursion at Universität Hamburg.
  """
  from os.path import dirname, join
  
  from . import csv
  from . import math
  from . import plots
  from . import utils
  
  
  __version__ = open(join(dirname(__file__), 'VERSION')).read().strip()
  
  __all__ = [
      'csv',
      'math',
      'plots',
      'utils',
  ]
  
new_contents: # -*- coding: utf-8 -*-
  """Python package to support the research during
  the annual Lehrexkursion at Universität Hamburg.
  """
  from os.path import dirname, join
  
  from . import csv
  from . import math
  from . import plots
  from . import utils
  
  
  __version__ = open(join(dirname(__file__), 'VERSION')).read().strip()
  
  __all__ = [
      'csv',
      'math',
      'plots',
      'utils',
  ]
  
  
  class Test:
      def foo(self):
          return f"{self}"
  
  
  Test()
  
subject: Introduce Python 3.5 syntax error.