How could I extract prams(weight) information from static mod(tvm.IRModule) in python

Questions
1

the following is an example about how I get mod:

md                = "mobilenet_v1_1.0_224_original.onnx"
dict    = {input.0: [1,3,224,224]}
onnx_model = onnx.load(model_path)
mod, params = relay.frontend.from_onnx(onnx_model, dict, freeze_params=True) # for unknown shape

now params is empy {} how could I get params(weight) list and its shape for calculating total weight size to decide if my device has enough memory to handle this mod.

any suggestion?

thanks~~~