input: Write a python function to run a series of tests and print out a summary of the results.
  assert run_tests([{"name": "Test1", "run": lambda: 1==1}, {"name": "Test2", "run": lambda: 2==2}]) == "2 tests passed\n0 tests failed"
  assert run_tests([{"name": "Test1", "run": lambda: 1==0}, {"name": "Test2", "run": lambda: 2==2}]) == "1 tests passed\n1 tests failed"
output: def run_tests(tests):
      passed = 0
      failed = 0
      
      for test in tests:
          if test["run"]():
              passed += 1
          else:
              failed += 1
      
      return f"{passed} tests passed\n{failed} tests failed"