class_docstr: ExponentialFamily inherits from Distribution. ExponentialFamily is a base
  class for distributions whose density function has the form:
  p_F(x;\theta) = exp(
      <t(x), \theta> -
      F(\theta) +
      k(x)
  ) where
  t(x): sufficient statistics
  \theta: natural parameters
  F(\theta): log_normalizer
  k(x): carrier measure
docstr: Return a tuple that stores natural parameters of the distribution.
docstr_tok: ["Return","a","tuple","that","stores","natural","parameters","of","the","distribution","."]
code: def _natural_params(self):
      r"""
      Return a tuple that stores natural parameters of the distribution.
      """
      raise NotImplementedError
  
imports: from .distribution import Distribution
label_desc: Use image node_id 1 for calling the ExponentialFamily obj's underlying member method code with example usage: obj._natural_params() without return types