Add Python v3.9 to the Github workflow

.editorconfig

@@ -0,0 +1,12 @@
+# EditorConfig is awesome: https://EditorConfig.org
+
+# top-most EditorConfig file
+root = true
+
+[*.py]
+indent_style = space
+indent_size = 4
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true

.github/workflows/python-package.yml

@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.6, 3.7, 3.8]
+        python-version: [3.6, 3.7, 3.8, 3.9]
 
     steps:
     - uses: actions/checkout@v2

src/Alertify/config.py

@@ -30,13 +30,14 @@ class Config:
         logging.debug('Parsing config')
         parsed = {}
 
-        try:
-            with open(configfile, 'r') as file:
-                parsed = yaml.safe_load(file.read())
-        except FileNotFoundError as error:
-            logging.warning('No config file found (%s)', error.filename)
-        except TypeError:
-            logging.warning('No config file provided.')
+        if configfile is not None:
+            try:
+                with open(configfile, 'r') as file:
+                    parsed = yaml.safe_load(file.read())
+            except FileNotFoundError as error:
+                logging.warning('No config file found (%s)', error.filename)
+            except TypeError:
+                logging.warning('No config file provided.')
 
         # Iterate over the config defaults and check for environment variable
         #   overrides, then check for any items in the config, otherwise