code: def cdf(self, x):
      return 12 * (x**2 / 2 - x**3 / 3 + x**4 / 4)
  
imports: import numpy
  from .common import Benchmark, safe_import
label_desc: Use image node_id 4 for calling the contdist1 obj's underlying member method code with example usage: obj.cdf(x) and returns: unknown