Fix type related errors

tests/history/coursereg_history/test_cleaned_csvs.py

@@ -2,7 +2,8 @@
 import os
 import re
 import unittest
-from typing import Callable, Iterator, List
+from collections.abc import Iterator
+from typing import Callable
 
 
 def is_int(val: str) -> bool:
@@ -13,7 +14,7 @@ def is_int(val: str) -> bool:
         return False
 
 
-def has_good_header(reader: Iterator[List[str]], file_path: str) -> None:
+def has_good_header(reader: Iterator[list[str]], file_path: str) -> None:
     header_row = next(reader)
 
     expected_header = ["Faculty", "Department", "Code",
@@ -28,21 +29,21 @@ def has_good_header(reader: Iterator[List[str]], file_path: str) -> None:
                          f"{header_row} has incorrect column labels.")
 
 
-def has_good_length(reader: Iterator[List[str]], file_path: str) -> None:
+def has_good_length(reader: Iterator[list[str]], file_path: str) -> None:
     for row in reader:
         if len(row) != 13:
             raise ValueError(f"In {file_path}:"
                              f"{row} has too few/many entries.")
 
 
-def has_entries(reader: Iterator[List[str]], file_path: str) -> None:
+def has_entries(reader: Iterator[list[str]], file_path: str) -> None:
     for row in reader:
         if any(item == "" for item in row):
             raise ValueError(f"In {file_path}:"
                              f"{row} has empty entries.")
 
 
-def has_valid_course_codes(reader: Iterator[List[str]],
+def has_valid_course_codes(reader: Iterator[list[str]],
                            file_path: str) -> None:
     # Valid codes: LL5009GRSI, GESS1025
     course_code_pattern = r"^[A-Z]{2,4}\d{4}[A-Z]{0,4}$"
@@ -57,7 +58,7 @@ def has_valid_course_codes(reader: Iterator[List[str]],
                              f"{course_code} did not match the regex.")
 
 
-def has_number_data(reader: Iterator[List[str]], file_path: str) -> None:
+def has_number_data(reader: Iterator[list[str]], file_path: str) -> None:
     # Skip the header row
     next(reader)
 
@@ -67,7 +68,7 @@ def has_number_data(reader: Iterator[List[str]], file_path: str) -> None:
                              f"{row[5:]} did not have number data.")
 
 
-def check_all_csvs(check_func: Callable[[Iterator[List[str]], str],
+def check_all_csvs(check_func: Callable[[Iterator[list[str]], str],
                                         None]) -> bool:
     current_file_directory = os.path.dirname(os.path.abspath(__file__))
     csv_directory = os.path.abspath(