Can not install on Pop os 21.04 dependency issues

I can not install on Pop Os 21.04 because of dependency issues.

Here is installation log:

```
➜ ~ sudo apt install howdy
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
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.
libgphoto2-dev : Depends: libgphoto2-6 (= 2.5.26-2) but 2.5.27-1 is to be installed
libopenexr-dev : Depends: libopenexr25 (= 2.5.4-1) but 2.5.4-2 is to be installed
libpython3.9-dev : Depends: libpython3.9-stdlib (= 3.9.5-3~20.10.1) but 3.9.5-3 is to be installed
Depends: libpython3.9 (= 3.9.5-3~20.10.1) but 3.9.5-3 is to be installed
python3.9-dev : Depends: python3.9 (= 3.9.5-3~20.10.1) but 3.9.5-3 is to be installed
Depends: libpython3.9 (= 3.9.5-3~20.10.1) but 3.9.5-3 is to be installed
E: Unable to correct problems, you have held broken packages.
```

----

I've searched for similar issues already, and my issue has not been reported yet.

Linux's distribution: Pop 21.04 hirsute

Howdy version : Not installed

Start by reproducing `sudo apt install howdy` on Pop!_OS 21.04 using the dependency versions shown in the installation log. Investigate how Howdy's package dependencies are defined and identify a compatible set for this distribution. Done means the package installs successfully without the reported unmet dependencies.

Written by the indexing model from the issue text.