Run flake8 linter on python code (#474)

* Run-flake8-linter-on-Python-code

* Remove hardware/unicorn/scripts/checklib.js

.travis.yml

@@ -4,6 +4,19 @@ node_js:
   - "6"
   - "8"
   - "10"
+matrix:
+  include:
+    - python: 2.7
+      language: python
+      before_script: pip install flake8
+      script: flake8 . --count --select=E901,E999,F821,F822,F823 --show-source --statistics
+    - python: 3.7
+      language: python
+      dist: xenial    # required for Python 3.7 (travis-ci/travis-ci#9069)
+      sudo: required  # required for Python 3.7 (travis-ci/travis-ci#9069)
+      before_script: pip install flake8
+      script: flake8 . --count --select=E901,E999,F821,F822,F823 --show-source --statistics
+    
 before_script:
   # Remove the './node_modules/.bin:' entry, see https://github.com/travis-ci/travis-ci/issues/8813
   - npm i -g npm

hardware/unicorn/scripts/checklib.js

@@ -1,13 +0,0 @@
-#!/usr/bin/env node
-var fs =  require('fs');
-
-if (!fs.existsSync('/usr/local/lib/python2.7/dist-packages/unicornhat.py')) {
-    console.warn("WARNING : Can't find required python library");
-    console.warn("WARNING : Please install using the following command");
-    console.warn("WARNING : Note: this uses root...");
-    console.warn("WARNING :    curl -sS get.pimoroni.com/unicornhat | bash\n");
-    //process.exit(1);
-}
-else {
-    console.log("Python library found OK.\n")
-}

hardware/unicorn/unihat.py

@@ -2,13 +2,19 @@
 
 # Import library functions we need
 from __future__ import print_function
-import sys
-import os
-import unicornhat as UH
 
-if sys.version_info >= (3,0):
-    print("Sorry - currently only configured to work with python 2.x")
-    sys.exit(1)
+import sys
+
+try:
+    import unicornhat as UH
+except ImportError:
+    print("run: pip install --user --upgrade unicornhat\n  before trying again.")
+    sys.exit(0)
+
+try:
+    raw_input          # Python 2
+except NameError:
+    raw_input = input  # Python 3
 
 brightness = float(sys.argv[1])/100
 UH.off()