docstr: random variables with Student T distribution
  
  Parameters
  ----------
  size : int or tuple
      the number and shape of random variables to draw.
  
  Returns
  -------
  rvs : ndarray
      the returned random variables with shape given by size and the
      dimension of the multivariate random vector as additional last
      dimension
      - TODO: Not sure if this works for size tuples with len>1.
  
  Notes
  -----
  generated as a chi-square mixture of multivariate normal random
  variables.
  does this require df>2 ?
code: def rvs(self, size=1):
      """random variables with Student T distribution
  
      Parameters
      ----------
      size : int or tuple
          the number and shape of random variables to draw.
  
      Returns
      -------
      rvs : ndarray
          the returned random variables with shape given by size and the
          dimension of the multivariate random vector as additional last
          dimension
          - TODO: Not sure if this works for size tuples with len>1.
  
      Notes
      -----
      generated as a chi-square mixture of multivariate normal random
      variables.
      does this require df>2 ?
  
  
      """
      from .multivariate import multivariate_t_rvs
  
      return multivariate_t_rvs(
          self.mean, self.sigma, df=self.df, n=size
      )
  
imports: import numpy
  from scipy import special
  from statsmodels.sandbox.distributions.multivariate import mvstdtprob
  from .extras import mvnormcdf
label_desc: Use image node_id 2 for calling the MVT obj's underlying member method code with example usage: obj.rvs(size) and returns: multivariate_t_rvs