code: def _grad_projection(self, grad1, grad2):
      grad2 = grad2 / np.linalg.norm(grad2)
      gtemp = grad1 - np.sum(grad1 * grad2) * grad2
      gtemp /= np.linalg.norm(gtemp)
      return gtemp
  
imports: import numpy
  from sklearn.base import TransformerMixin
  from sklearn.utils.validation import assert_all_finite
  from .base_metric import _PairsClassifierMixin, MahalanobisMixin
  from .constraints import Constraints, wrap_pairs
  from ._util import components_from_metric, _initialize_metric_mahalanobis
  import warnings
label_desc: Use image node_id 8 for calling the _BaseMMC obj's underlying member method code with example usage: obj._grad_projection(grad1, grad2) and returns: gtemp