Improve username behavior

Course3/Lab4/validations.py

@@ -1,24 +1,28 @@
 #!/usr/bin/env python3
-
+ 
 import re
-
+ 
 def validate_user(username, minlen):
     """Checks if the received username matches the required conditions."""
     if type(username) != str:
         raise TypeError("username must be a string")
     if minlen < 1:
         raise ValueError("minlen must be at least 1")
-    
+
     # Usernames can't be shorter than minlen
     if len(username) < minlen:
         return False
     # Usernames can only use letters, numbers, dots and underscores
-    if not re.match('^[a-z0-9._]*$', username):
+    if not re.match('^[a-z][a-z0-9._]*$', username):
         return False
     # Usernames can't begin with a number
     if username[0].isnumeric():
         return False
     return True
 
 
+print(validate_user("blue.kale", 3)) # True
+print(validate_user(".blue.kale", 3)) # Currently True, should be False
+print(validate_user("red_quinoa", 4)) # True
+print(validate_user("_red_quinoa", 4)) # Currently True, should be False