Interpolation not performed in dictionary

[Ching-Hwa Yu]

conf.py

var = {"a": "{var1}"}

dir/conf.py

var1 = "test"

code:

module_list = ["dir/conf.py", "conf.py"]
cfg = config(*module_list, interpolate=True)
print(cfg.var)

Result is:
{'a': '{var1}'}