NAdam
class torch.optim.NAdam(params, lr=0.002, betas=(0.9, 0.999), eps=1e-08, weight_decay=0, momentum_decay=0.004, *, foreach=None, differentiable=False)
Implements NAdam algorithm.
  \begin{aligned}      &\rule{110mm}{0.4pt}
  \\      &\textbf{input}      : \gamma_t \text{ (lr)}, \:
  \beta_1,\beta_2 \text{ (betas)},          \: \theta_0 \text{
  (params)}, \: f(\theta) \text{ (objective)}                   \\
  &\hspace{13mm} \: \lambda \text{ (weight decay)}, \:\psi \text{
  (momentum decay)}    \\      &\textbf{initialize} :  m_0
  \leftarrow 0 \text{ ( first moment)},          v_0 \leftarrow 0
  \text{ ( second moment)}
  \\[-1.ex]      &\rule{110mm}{0.4pt}
  \\      &\textbf{for} \: t=1 \: \textbf{to} \: \ldots \:
  \textbf{do}                         \\      &\hspace{5mm}g_t
  \leftarrow   \nabla_{\theta} f_t (\theta_{t-1})           \\
  &\hspace{5mm}if \: \lambda \neq 0
