Prefer __spec__ on modern python

Python 3.1x moves on to replace __file__ and __package__ entirely by __spec__.
This commit ensures to keep up and avoid issues with former 2 being no longer
maintained or even removed at some point in future.

Author: deathaxe

package_control/sys_path.py

@@ -16,7 +16,12 @@
 if not os.path.isdir(__default_packages_path):
     # Fall back to detecting the path using the location of the module
     import Default.sort as default_module
-    __default_packages_path = os.path.dirname(os.path.dirname(default_module.__file__))
+    try:
+        # python 3.8+
+        __default_packages_path = os.path.dirname(os.path.dirname(default_module.__spec__.origin))
+    except AttributeError:
+        # python 3.3
+        __default_packages_path = os.path.dirname(os.path.dirname(default_module.__file__))
 
 if not os.path.isdir(__default_packages_path):
     raise FileNotFoundError('Default Packages')
@@ -28,7 +33,12 @@
 # {data_dir}/Installed Packages/Package Control.sublime-package/package_control/sys_path.py
 # When loaded as unpacked package, __file__ ends up being
 # {data_dir}/Packages/Package Control/package_control/sys_path.py
-__data_path = os.path.dirname(os.path.dirname(os.path.dirname(os.path.dirname(__file__))))
+try:
+    # python 3.8+
+    __data_path = os.path.dirname(os.path.dirname(os.path.dirname(os.path.dirname(__spec__.origin))))
+except AttributeError:
+    # python 3.3
+    __data_path = os.path.dirname(os.path.dirname(os.path.dirname(os.path.dirname(__file__))))
 
 # Determine extracted packages path
 __packages_path = os.path.join(__data_path, 'Packages')