You’re trying to concatenate a string and an integer, which is incorrect.
Change print(numlist.pop(2)+" has been removed") to any of these:
Explicit int to str conversion:
print(str(numlist.pop(2)) + " has been removed")
Use , instead of +:
print(numlist.pop(2), "has been removed")
String formatting:
print("{} has been removed".format(numlist.pop(2)))