+------------------------------------------------------------------------------+
| Install curtin build dependencies (apt-based resolver)                       |
+------------------------------------------------------------------------------+

Installing build dependencies
Reading package lists...
Building dependency tree...
Reading state information...
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 sbuild-build-depends-curtin-dummy : Depends: python3-pyflakes but it is not installable
E: Unable to correct problems, you have held broken packages.
apt-get failed.
Package installation failed
Not removing build depends: cloned chroot in use

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| Cleanup                                                                      |
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Purging /<<BUILDDIR>>
Not cleaning session: cloned chroot in use
E: Package build dependencies not satisfied; skipping