check against `FORMAT_VERSION_TEMPLATE`, drop the silly braces:

```python
if not len(self.VERSION.version) == len(FORMAT_VERSION_TEMPLATE.split('.')):
    self.log.error('Invalid version number %s' % self.VERSION)
```

Also, isn't there some magic function we can implement in `EasyVersion` such that `len(self.VERSION)` does what you want? Now you're showing EasyVersion's guts, which is not the best things to do.