DirectPython constants module. Most constants are directly from SDK-headers. Certain prefixes are usually removed, for example D3D11_BLEND_ZERO in C-code would be BLEND_ZERO (the D3D11_-prefix is removed) in DirectPython. All .fx-files use the same notation.
This module is usually imported with from d3d11 import *, but you don’t have to if you don’t want to clutter your namespace. You can use import d3d11c and access them by their module name (d3d11c.BLEND_ZERO).