Raise minimum python version to 3.8 (#3176)

script/lint-python

@@ -1,7 +1,13 @@
 #!/usr/bin/env python3
 
-from __future__ import print_function
-from helpers import styled, print_error_for_file, get_output, get_err, git_ls_files, filter_changed
+from helpers import (
+    styled,
+    print_error_for_file,
+    get_output,
+    get_err,
+    git_ls_files,
+    filter_changed,
+)
 import argparse
 import colorama
 import os
@@ -34,6 +40,12 @@ def main():
     parser.add_argument(
         "-c", "--changed", action="store_true", help="Only run on changed files"
     )
+    parser.add_argument(
+        "-a",
+        "--apply",
+        action="store_true",
+        help="Apply changes to files where possible",
+    )
     args = parser.parse_args()
 
     files = []
@@ -56,7 +68,7 @@ def main():
 
     errors = 0
 
-    cmd = ["black", "--verbose", "--check"] + files
+    cmd = ["black", "--verbose"] + ([] if args.apply else ["--check"]) + files
     print("Running black...")
     print()
     log = get_err(*cmd)
@@ -97,6 +109,21 @@ def main():
         print_error(file_, linno, msg)
         errors += 1
 
+    PYUPGRADE_TARGET = "--py38-plus"
+    cmd = ["pyupgrade", PYUPGRADE_TARGET] + files
+    print()
+    print("Running pyupgrade...")
+    print()
+    log = get_err(*cmd)
+    for line in log.splitlines():
+        REWRITING = "Rewriting"
+        if line.startswith(REWRITING):
+            file_ = line[len(REWRITING) + 1 :]
+            print_error(
+                file_, None, f"Please run pyupgrade {PYUPGRADE_TARGET} on this file"
+            )
+            errors += 1
+
     sys.exit(errors)