minor: typo and code style

src/_pytest/fixtures.py

@@ -1013,7 +1013,7 @@ class FixtureFunctionMarker(object):
 
     def __call__(self, function):
         if isclass(function):
-            raise ValueError("class fixtures not supported (may be in the future)")
+            raise ValueError("class fixtures not supported (maybe in the future)")
 
         if getattr(function, "_pytestfixturefunction", False):
             raise ValueError(
@@ -1366,8 +1366,7 @@ class FixtureManager(object):
             fixturedefs = self._arg2fixturedefs[argname]
         except KeyError:
             return None
-        else:
-            return tuple(self._matchfactories(fixturedefs, nodeid))
+        return tuple(self._matchfactories(fixturedefs, nodeid))
 
     def _matchfactories(self, fixturedefs, nodeid):
         for fixturedef in fixturedefs:

src/_pytest/main.py

@@ -564,9 +564,7 @@ class Session(nodes.FSCollector):
         return True
 
     def _tryconvertpyarg(self, x):
-        """Convert a dotted module name to path.
-
-        """
+        """Convert a dotted module name to path."""
         try:
             with _patched_find_module():
                 loader = pkgutil.find_loader(x)
@@ -598,8 +596,7 @@ class Session(nodes.FSCollector):
                 raise UsageError(
                     "file or package not found: " + arg + " (missing __init__.py?)"
                 )
-            else:
-                raise UsageError("file not found: " + arg)
+            raise UsageError("file not found: " + arg)
         parts[0] = path
         return parts