Merge Fields

>>> from techminer2.database.field_operators import MergeFieldsOperator
>>> (
...     MergeFieldsOperator()  
...     #
...     # FIELDS:
...     .with_field["author_keywords", "index_keywords"])
...     .with_other_field("merged_keywords")
...     #
...     # DATABASE:
...     .where_root_directory_is("example/")
...     #
...     .run()
... )