1  from plates import is_valid
 2  
 3  def test_letters():
 4      assert is_valid("993") == False
 5      assert is_valid("AAB34") == True
 6  
 7  def test_minmax():
 8      assert is_valid("A") == False
 9      assert is_valid("AA12345") == False
10      assert is_valid("AA1234") == True
11      assert is_valid("AA") == True
12  
13  def test_alnum():
14      assert is_valid("AA123!") == False
15      assert is_valid("AA1234") == True
16      assert is_valid("AA12a") == False
17      assert is_valid("AA12a!") == False
18  
19  def test_num():
20      assert is_valid("AA0123") == False
21      assert is_valid("AA1234") == True
22      assert is_valid("AA123a") == False
23  
24