This line could be simplified to:

```python
if sys.argv[1] in REPORT_TAGS[0:3]:
```

You could even force it to do a lowercase to avoid someone passing uppercase or a combination of lower/upper.

```python
if sys.argv[1].lower() in REPORT_TAGS[0:3]:
```

I'd really recommend saving ```sys.argv[1]``` into a more meaningful variable name so that it is easier to follow it. :)