message: Updated the Math block to match the alignment.
diff: @@ -47,10 +47,10 @@ class Ftrl(optimizer_v2.OptimizerV2):
  $$n_{t,i} = n_{t-1,i} + g_{t,i}^{2}$$
  $$\sigma_{t,i} = (\sqrt{n_{t,i}} - \sqrt{n_{t-1,i}}) / \alpha$$
  $$z_{t,i} = z_{t-1,i} + g_{t,i} - \sigma_{t,i} * w_{t,i}$$
  - $$w_{t,i} =\begin{cases}
  -0 & | z_{i}| \leqslant \lambda _{1} ,\\
  -\ -\left(\frac{\beta +\sqrt{n_{t,i}}}{\alpha } +\lambda _{2}\right)^{-1}( z_{i} -sgn(z_{i} )*\lambda _{1}) & otherwise.
  -\end{cases}$$
  + $$w_{t,i} =\begin{cases} 0 & | z_{i}| \leqslant \lambda _{1} ,\\
  + \ -\left(\frac{\beta +\sqrt{n_{t,i}}}{\alpha }
  + +\lambda _{2}\right)^{-1}( z_{i} -sgn(z_{i} )
  + *\lambda _{1}) & otherwise.\end{cases}$$
  Check the documentation for the l2_shrinkage_regularization_strength
  parameter for more details when shrinkage is enabled, in which case gradient
  