class_docstr: Instance of the pricing problem.
  
  For more details, see:
  
  Dash, S., Gunluk, O., and Wei, D. (2018). Boolean decision rules via column generation.
  In Bengio, S., Wallach, H., Larochelle, H., Grauman, K., Cesa- Bianchi, N.,
  and Garnett, R., editors, Advances in Neural Information Processing Systems 31,
  pages 4660–4670. Curran Associates, Inc.
code: def __init__(self, rp, rn, Xp, Xn, v0, z0):
      self.rp = rp
      self.rn = rn
      self.Xp = Xp
      self.Xn = Xn
      self.v0 = v0
      self.z0 = z0
  
imports: import numpy
  import pandas
label_desc: Use image node_id 1 to create a new PricingInstance object  with example: obj = PricingInstance(rp, rn, Xp, Xn, v0, z0)