Add Python version detection and report error when using incompatible version #325

Author: screamerbg

mbed/mbed.py

@@ -2335,6 +2335,11 @@ def main():
 
     # Help messages adapt based on current dir
     cwd_root = os.getcwd()
+ 
+    if sys.version_info[0] != 2 or sys.version_info[1] < 7:
+        error(
+            "mbed CLI is compatible with Python version >= 2.7 and < 3.0\n"
+            "Please refer to the online guide available at https://github.com/ARMmbed/mbed-cli")
 
     # Parse/run command
     if len(sys.argv) <= 1: