code: def get_mean_and_stddevs(self, sites, rup, dists, imt, stddev_types):
          # pylint: disable=too-many-arguments
          
  
          # obtain coefficients for required intensity measure type (IMT)
          coeffs = self.COEFFS_BEDROCK[imt].copy()
  
          # obtain IMT-independent coefficients
          coeffs.update(self.CONSTS)
  
          # compute bedrock motion, equation (11)
          ln_mean = self._compute_mean(rup, dists, coeffs)
  
          # obtain standard deviation
          ln_stddev = self._get_stddevs(coeffs, stddev_types)
  
          return ln_mean, [ln_stddev]
docs: See :meth:`superclass method
          <.base.GroundShakingIntensityModel.get_mean_and_stddevs>`
          for specification of input and result values.
  
          Implements equation (11) on p. 484:
  
          ``ln(P) = c1 + c2*M + c3*(10 - M)^3 + c4*ln(R + c5*exp(c6*M)``