Hello!
The default installation of SageMath was updated today. This means it
changed from 7.3 to 7.5.
* If you still want to use 7.3, run "sage_select 7.3" in a terminal or
the small "mini terminal" in files.
* In case you notice any problems, please email us at
he...@sagemath.com or comment here. We do keep track of all
additionally installed packages and Python libraries, but this doesn't
mean there are no subtle problems in the details.
* Documentation:
http://doc.sagemath.org/html/en/
--
Harald Schilly -- SageMath, Inc.
https://cloud.sagemath.com