I'm trying to figure out why my code doesn't work when I'm trying to print a collection of strings. In Python 2 I could usually do:

```
print ('test is') + ('this')

```

However, in Python 3 it prodcues the following error:

```
TypeError: unsupported operand type(s) for +: 'NoneType' and 'str'

```

I have tried replacing '+' with 'and' which works but the string doesn't come out after that. Can someone please explain to me how and why?