manually clean up some python 3.6 era code

mesonbuild/mesonlib/universal.py

@@ -1708,9 +1708,7 @@ class OrderedSet(T.MutableSet[_T]):
     insertion.
     """
     def __init__(self, iterable: T.Optional[T.Iterable[_T]] = None):
-        # typing.OrderedDict is new in 3.7.2, so we can't use that, but we can
-        # use MutableMapping, which is fine in this case.
-        self.__container = collections.OrderedDict()  # type: T.MutableMapping[_T, None]
+        self.__container: T.OrderedDict[_T, None] = collections.OrderedDict()
         if iterable:
             self.update(iterable)
 
@@ -1741,12 +1739,10 @@ class OrderedSet(T.MutableSet[_T]):
             del self.__container[value]
 
     def move_to_end(self, value: _T, last: bool = True) -> None:
-        # Mypy does not know about move_to_end, because it is not part of MutableMapping
-        self.__container.move_to_end(value, last) # type: ignore
+        self.__container.move_to_end(value, last)
 
     def pop(self, last: bool = True) -> _T:
-        # Mypy does not know about the last argument, because it is not part of MutableMapping
-        item, _ = self.__container.popitem(last)  # type: ignore
+        item, _ = self.__container.popitem(last)
         return item
 
     def update(self, iterable: T.Iterable[_T]) -> None:

unittests/allplatformstests.py

@@ -3186,11 +3186,6 @@ class AllPlatformTests(BasePlatformTests):
         expected_lines = expected.split('\n')[1:]
         out_start = out.find(expected_lines[0])
         out_lines = out[out_start:].split('\n')[:len(expected_lines)]
-        if sys.version_info < (3, 7, 0):
-            # Dictionary order is not stable in Python <3.7, so sort the lines
-            # while comparing
-            expected_lines = sorted(expected_lines)
-            out_lines = sorted(out_lines)
         for e, o in zip(expected_lines, out_lines):
             if e.startswith('    external dep'):
                 self.assertRegex(o, r'^    external dep   : (YES [0-9.]*|NO)$')