text: Title: Can't import into Google Colab
  Body: While trying to import into Google Colab using ```import vectorbt as vbt ```  when```PyYAML``` version 6 is used, I get the error message:
  
  ```
  [/usr/local/lib/python3.7/dist-packages/distributed/config.py](https://localhost:8080/#) in <module>()
       18 
       19 with open(fn) as f:
  ---> 20     defaults = yaml.load(f)
       21 
       22 dask.config.update_defaults(defaults)
  
  TypeError: load() missing 1 required positional argument: 'Loader'
  ```
  
  Is there anyway to use vectorbt with PyYAML 6 ?