code: def _pdf(self, x, a, b):
      return exp(self._logpdf(x, a, b))
  
file_path: statsmodels/statsmodels/sandbox/examples/bayesprior.py
imports: import numpy
  from matplotlib import pyplot
  from scipy import stats, integrate
  from scipy.stats import rv_continuous
  from scipy.special import gammaln, gammaincinv, gammainc
  from numpy import log, exp
label_desc: Use image node_id 1 for calling the igamma_gen obj's underlying member method code with example usage: obj._pdf(x, a, b) and returns: exp