old_contents: 
  import pytest
  
  
  def test_read_file():
      from trigrams import read_file
      lines = read_file()
      assert len(lines) > 0
  
  
new_contents: # -*- coding: utf-8 -*-
  import pytest
  
  
  def test_read_file():
      """Assert the file imported and was split into lines."""
      from trigrams import read_file
      assert len(read_file()) > 0
  
  
subject: Refactor test file