AQL query: count of document returned

Hi,

when I execute a query as:

```
cursor = my_db.execute_query(
  "FOR d IN my_col FILTER d.value == 'value' RETURN d"
)
```

How can I know if the resultset has values or is empty?
If I try to do:

```
for doc in cursor:
  print doc
```

I get this error:
`'generator' object has no attribute 'current'`

Thanks for your help.
M.
