About torch.fx: Is there a way to convert Proxy to base type?

Is there a way to convert Proxy to base type?
such as :

import torch
import torch.nn as nn
from torch.fx import symbolic_trace

class M(nn.Module):
  def __init__(self):
    super().__init__()
  def forward(self, x):
    x = x.size(1)
    a = torch.randn(x)
    return a
m = M()

symbolic_trace(m)

while the type of x is Proxy, and the function randn can’t use Proxy.

So, I need to convert Proxy to int type.

please help me, thanks a lot.