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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def query_revisions_by_revids(session, revids, **params):
 """ Gets a set of revisions by their IDs by repeatedly querying in batches. If an ID cannot be found, it is ignored. """

    doc = session.get(action='query', prop='revisions',
                      revids=revids, **params)

    for page_doc in doc['query'].get('pages', {}).values():
        revisions = page_doc.get('revisions', [])
        if 'revisions' in page_doc:
            del page_doc['revisions']

        for revision_doc in revisions:
            revision_doc['page'] = page_doc
            yield revision_doc