function input(config) {
	  return Input(config);
	}
Used to instantiate an input to a model as a `tf.SymbolicTensor`.

Users should call the `input` factory function for
consistency with other generator functions.

Example:

```js
// Defines a simple logistic regression model with 32 dimensional input
// and 3 dimensional output.
const x = tf.input({shape: [32]});
const y = tf.layers.dense({units: 3, activation: 'softmax'}).apply(x);
const model = tf.model({inputs: x, outputs: y});
model.predict(tf.ones([2, 32])).print();
```

Note: `input` is only necessary when using `model`. When using
`sequential`, specify `inputShape` for the first layer or use `inputLayer`
as the first layer.

@doc {heading: 'Models', subheading: 'Inputs'}