check for RPi.GPIO which is a dependancy for:

Adafruit_Blinka/src/adafruit_blinka/microcontroller/bcm283x/pin.py

raspi-blinka.py

@@ -62,8 +62,9 @@ def update_pip():
 def install_blinka():
     print("Installing latest version of Blinka locally")
     shell.run_command("sudo apt-get install -y i2c-tools")
+    shell.run_command("pip3 install --upgrade RPi.GPIO")
     shell.run_command("pip3 install --upgrade adafruit-blinka")
-    
+
 def main():
     global default_python
     shell.clear()