With IronPython you can access any .net assembly which is compiled using the same or a lower version than the IronPython core.
Example: Importing a a .net assembly and class
from System import Math
Example: Using an imported class:
from System import Math
print Math.Abs(-123)
You can also load additional assemblies by using the builtin clr
module.
import clr
clr.AddReference('Sample') # Sample.dll inside of the working directory.
Than just use it as any other .net or python library.