code: def residual(p):
      return (
          p["a1"] * np.exp(-x / p["t1"])
          + p["a2"] * np.exp(-(x - 0.1) / p["t2"])
          - y
      )
  
imports: import matplotlib.pyplot
  import numpy
  import lmfit
label_desc: Use image node_id 1 for calling a global function with example usage: residual(p) and returns: unknown