Xavier Morel
3de97f1689
Attempt to clarify/improve error message (and avoid traceback) when
import fails due to some intermediate system e.g. memory error or
gateway timeout.
Task 38254
Closes #20627
This change is loosely related to
35d452cffb and PR #24854 in the sense
that that was an attempt to better handle transport/gateway issues
during file download.