docstr: Multiplies grads by a constant *c*.
docstr_tok: ["Multiplies","grads","by","a","constant","*","c","*","."]
code: def multiply_grads(self, c):
      """Multiplies grads by a constant *c*."""
      for p in self.params:
          if p.grad is not None:
              p.grad.data.mul_(c)
  
imports: import torch
  from fairseq.utils import clip_grad_norm_
  from pytext.config import ConfigBase
  from pytext.config.component import Component, ComponentType
label_desc: Use image node_id 5 for calling the Optimizer obj's underlying member method code with example usage: obj.multiply_grads(c) without return types