I tried everything you suggested and I now get a different error:
</s>Traceback (most recent call last):
File "grove_moisture_sensor.py", line 61, in <module>
print(grovepi.analogRead(sensor))
File "/home/pi/Dexter/GrovePi/Software/Python/grovepi.py", line 227, in analogRead
return number[1] * 256 + number[2]
TypeError: 'int' object has no attribute '__getitem__'
<e>