title: Unittest is running enitre python file instead of single funciton
body: <p>Im writing some unittests for a simple addition program.</p>
  <pre><code>def add(int1, int2):
  a = int1 + int2
  return (a)
  
  def run():
      int1 = int(input())
      int2 = int(input())
      ans = add(int1, int2)
      print(ans)
  run()
  </code></pre>
  <p>But when I run the testing script below on cmd line, it runs the &quot;run()&quot; function and then runs the testing script. I feel like I'm missing something simple here. Any help?</p>
  <pre><code>import unittest
  from simpleaddition import add
  
  class Test_Addition(unittest.TestCase): #first test will check an increase in num digits
      def test_Inc(self):
          ans = add(99, 1)
          self.assertEqual(ans, 100)
  
      def test_Hard(self): #testing on hard coded/assigned digit
          testDigit = 5555
          testNum = 4444
          testAns = 9999
          ans = add(testDigit, testNum)
          self.assertEqual(ans, testAns)
  
      def test_Assign(self): #should show that func will only add ints
          num1 = '5555'
          num2 = '4444'
          testAns = 9999
          ans = add(num1, num2)
          self.assertNotEqual(testAns, and)
  
  if __name__ == '__main__':
      unittest.main()
  </code></pre>