Function read 

pub fn read<T: TryFromBytes, P: TryFromBytes>(
    path: &str,
    example_size: usize,
) -> Result<(Array2<T>, Array2<P>), Box<dyn Error>>

Reads from dense file.

Returns (data,labels).

use ndarray::{Array2,array};

let data: Array2<u8> = array![[0, 0], [1, 0], [0, 1], [1, 1]];
let labels: Array2<u16> = array![[0], [1], [1], [0]];

dense::write("dense_reader",&data,&labels).unwrap();

let (read_data,read_labels) = dense::read::<u8,u16>("dense_reader",2).unwrap();

assert_eq!(read_data,data);
assert_eq!(read_labels,labels);