Last tested: Jun 12, 2018
Yep, you can configure a visualization of a query using the query.vis_config property. First call create_query to create a new query with the desired visualization, then create a new look or update an existing look to assign the id of the query you created to the look's query_id property. (look.query is read-only)
The content of vis_config varies with each visualization type and is not documented. The best way to figure out what vis_config properties to set to get a particular visualization is to configure a visualization in the Looker UI then use the API to see the resulting query.vis_config properties.
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