Mongo error sort
using this
https://www.quackit.com/mongodb/tutorial/mongodb_sort_query_results.cfm
But got error. column phase is exist

```python
collection.find( ).sort( { phase: 1 } )

```
Traceback (most recent call last):
  File "table2.py", line 37, in <module>
    collection.find( ).sort( { phase: 1 } )
NameError: name 'phase' is not defined

