code: def _calc_tau_1(self, x, loss):
      norm = utils.math.norm(x, order=2) ** 2
      if norm > 0:
          return min(self.C, loss / norm)
      return 0
  
imports: from __future__ import annotations
  import collections
  import numpy
  from river import base, optim, utils
label_desc: Use image node_id 3 for calling the BasePA obj's underlying member method code with example usage: obj._calc_tau_1(x, loss) and returns: int, min