code: def flatten(inputs, name=None, data_format="channels_last"):
      """Flattens an input tensor while preserving the batch axis (axis 0).
  
      Args:
        inputs: Tensor input.
        name: The name of the layer (string).
        data_format: A string, one of `channels_last` (default) or `channels_first`.
          The ordering of the dimensions in the inputs.
          `channels_last` corresponds to inputs with shape
          `(batch, height, width, channels)` while `channels_first` corresponds to
          inputs with shape `(batch, channels, height, width)`.
  
      Returns:
        Reshaped tensor.
  
      Examples:
  
      ```
        x = tf.compat.v1.placeholder(shape=(None, 4, 4), dtype='float32')
        y = flatten(x)
        # now `y` has shape `(None, 16)`
  
        x = tf.compat.v1.placeholder(shape=(None, 3, None), dtype='float32')
        y = flatten(x)
        # now `y` has shape `(None, None)`
      ```
      """
      warnings.warn(
          "`tf.layers.flatten` is deprecated and "
          "will be removed in a future version. "
          "Please use `tf.keras.layers.Flatten` instead."
      )
      layer = Flatten(name=name, data_format=data_format)
      return layer.apply(inputs)
  
file_path: tensorflow/tensorflow/python/keras/legacy_tf_layers/core.py
imports: import warnings
  from tensorflow.python.keras import layers
  from tensorflow.python.keras.legacy_tf_layers import base
  from tensorflow.python.ops import init_ops
label_desc: Use image node_id 3 for calling a global function with example usage: flatten(inputs, name, data_format) and returns: layer