code: def _nonnegative_float(v):
      try:
          v = float(v)
      except ValueError:
          raise argparse.ArgumentTypeError("invalid float: %r" % v)
      if not (v >= 0):  # no NaNs, please
          raise argparse.ArgumentTypeError(
              "must be non-negative: %r" % v
          )
      return v
  
imports: import argparse
  import functools
  import gzip
  import io
  import mimetypes
  import posixpath
  import zipfile
  from werkzeug import utils
  from werkzeug import wrappers
  from tensorboard import plugin_util
  from tensorboard.backend import http_util
  from tensorboard.plugins import base_plugin
  from tensorboard.util import grpc_util
  from tensorboard.util import tb_logging
  from tensorboard import version
label_desc: Use image node_id 3 for calling a global function with example usage: _nonnegative_float(v) and returns: v