code: def _compute_support(ytrue, labels=None, weights=None):
      if labels is not None:
          labels = set(labels)
          found = np.array([y in labels for y in ytrue], dtype=bool)
          ytrue = ytrue[found]
          if weights is not None:
              weights = weights[found]
  
      if weights is not None:
          support = np.sum(weights)
      else:
          support = ytrue.size
  
      return support
  
file_path: fiftyone/fiftyone/utils/eval/base.py
imports: import itertools
  import numpy
  import sklearn.metrics
  import fiftyone.core.evaluation
  import fiftyone.core.plots
label_desc: Use image node_id 3 for calling a global function with example usage: _compute_support(ytrue, labels, weights) and returns: support