code: def _forward(self, x):
      x = self._l0(x)
      x = self._l1(x)
      return x
  
imports: import os
  from hypothesis import given, strategies
  import numpy
  import ivy
  from ivy.functional.ivy.gradients import _variable
  import ivy_tests.test_ivy.helpers
label_desc: Use image node_id 2 for calling the DoubleLinear obj's underlying member method code with example usage: obj._forward(x) and returns: x