Meta: Resolve some pylint violations in Python lint scripts

Resolves:

* all: consider-using-sys-exit
* all: wrong-import-order
* all: TODO: Require that a few keys are set? (fixme)
* some: missing-function-docstring
* some: line-too-long

Meta/check-newlines-at-eof.py

@@ -4,57 +4,64 @@ import os
 import subprocess
 import sys
 
-os.chdir(os.path.dirname(__file__) + "/..")
 
-files = subprocess.run(
-    [
-        "git", "ls-files", "--",
-        "*.cpp",
-        "*.h",
-        "*.gml",
-        "*.html",
-        "*.js",
-        "*.css",
-        "*.sh",
-        "*.py",
-        "*.json",
-        "CMake*.txt",
-        "**/CMake*.txt",
-        ":!:AK/Tests/*.json",
-        ":!:Kernel/FileSystem/ext2_fs.h",
-        ":!:Userland/Libraries/LibELF/exec_elf.h"
-    ],
-    capture_output=True
-).stdout.decode().strip('\n').split('\n')
+def run():
+    """Check files checked in to git for trailing newlines at end of file."""
+    files = subprocess.run(
+        [
+            "git", "ls-files", "--",
+            "*.cpp",
+            "*.h",
+            "*.gml",
+            "*.html",
+            "*.js",
+            "*.css",
+            "*.sh",
+            "*.py",
+            "*.json",
+            "CMake*.txt",
+            "**/CMake*.txt",
+            ":!:AK/Tests/*.json",
+            ":!:Kernel/FileSystem/ext2_fs.h",
+            ":!:Userland/Libraries/LibELF/exec_elf.h"
+        ],
+        check=True,
+        capture_output=True
+    ).stdout.decode().strip('\n').split('\n')
 
-no_newline_at_eof_errors = []
-blank_lines_at_eof_errors = []
+    no_newline_at_eof_errors = []
+    blank_lines_at_eof_errors = []
 
-did_fail = False
-for filename in files:
-    with open(filename, "r") as f:
-        f.seek(0, os.SEEK_END)
+    did_fail = False
+    for filename in files:
+        with open(filename, "r") as f:
+            f.seek(0, os.SEEK_END)
 
-        f.seek(f.tell() - 1, os.SEEK_SET)
-        if f.read(1) != '\n':
-            did_fail = True
-            no_newline_at_eof_errors.append(filename)
-            continue
-
-        while True:
-            f.seek(f.tell() - 2, os.SEEK_SET)
-            char = f.read(1)
-            if not char.isspace():
-                break
-            if char == '\n':
+            f.seek(f.tell() - 1, os.SEEK_SET)
+            if f.read(1) != '\n':
                 did_fail = True
-                blank_lines_at_eof_errors.append(filename)
-                break
+                no_newline_at_eof_errors.append(filename)
+                continue
 
-if no_newline_at_eof_errors:
-    print("Files with no newline at the end:", " ".join(no_newline_at_eof_errors))
-if blank_lines_at_eof_errors:
-    print("Files that have blank lines at the end:", " ".join(blank_lines_at_eof_errors))
+            while True:
+                f.seek(f.tell() - 2, os.SEEK_SET)
+                char = f.read(1)
+                if not char.isspace():
+                    break
+                if char == '\n':
+                    did_fail = True
+                    blank_lines_at_eof_errors.append(filename)
+                    break
 
-if did_fail:
-    sys.exit(1)
+    if no_newline_at_eof_errors:
+        print("Files with no newline at the end:", " ".join(no_newline_at_eof_errors))
+    if blank_lines_at_eof_errors:
+        print("Files that have blank lines at the end:", " ".join(blank_lines_at_eof_errors))
+
+    if did_fail:
+        sys.exit(1)
+
+
+if __name__ == '__main__':
+    os.chdir(os.path.dirname(__file__) + "/..")
+    run()