code: def bc_flow(self, ya, yb, p):
      return np.array(
          [
              ya[0],
              ya[1],
              yb[0] - 1,
              yb[1],
              ya[3],
              yb[3],
              ya[5],
              yb[5] - 1,
          ]
      )
  
imports: import numpy
  from .common import Benchmark, safe_import
  from scipy.integrate import quad, cumulative_simpson
label_desc: Use image node_id 2 for calling the SolveBVP obj's underlying member method code with example usage: obj.bc_flow(ya, yb, p) and returns: np