Need approver name taken from DFF

Summary:

We have a requirement that the approver name is taken from a DFF.

Content (please ensure you mask any confidential information):

We have created a document record with a DFF capturing person from a LOV (all list of employees).

This DFF needs to be used in approval workflow as an approver. How can we configure a BPM approval rule that can take approver from that DFF?

Version (include the version you are using, if applicable):

26B

Code Snippet (add any code snippets that support your topic, if applicable):