Added snapshot_inv() and init_inv() to DepleteReactor.py

[SamarAbdelkawy]

Summary of changes

Following the issue of <explicit_inventory> flag in the input causes the core count to drop to zero every time step in the simulation, while this flag doesn't cause any issues in the C++ archetypes. I noticed two main functions that may be responsible to capture the inventory changes when this flag is on.

Two functions are SnapshotInv() and InitInv() as they exist in Cycamore archetypes, so I tried to follow the way they are defined inside Cycamore and added them to OpenMCyclus archetype.

Adding the functions fixed the issue of having an empty core suddenly in Tick, and now the count is correct, compared to running the simulation without the <explicit_inventory> flag at all.

One bug that still persists is that during the transmutation step, the fuel still doesn't go through the depletion step and jumps directly to discharging. My thoughts are that those two functions still need some edits, or to be defined in some other way to be able to capture the full functionality.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• I have read the CONTRIBUTING document.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

Associated Issues and PRs

• Issue: Not compatible with explicit_inventory option #23

Associated Developers

• Dev: @abachma2

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[abachma2]

I'll look more at the code next week, and see if I can figure out why the depletion solver isn't running. The unit tests aren't passing, and nothing in this PR should be causing them to fail; that might be something you can look at in the mean time (maybe needs to be a separate PR if it's unrelated to this one). Also, the CHANGELOG test is failing, because didn't update that for this PR.