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##### Summary
Fix: #4756
`python.d.plugin` updates:
* remove `retries` option
* make `penalty` configurable (enabled by default, max is 10 minutes)
> penalty indicates whether to apply penalty to update_every in case of failures.
> Penalty will increase every 5 failed updates in a row. Maximum penalty is 10 minutes.
> penalty: yes
##### Component Name
`python.d.plugin`
##### Additional Information
