def write_to_file(src, dst):
    """Write data from `src` into `dst`.

    Args:
        src (iterable): iterable that yields blocks of data to write
        dst (file-like object): file-like object that must support
            .write(block)

    Returns:
        number of bytes written to `dst`

    """
    n = 0
    for block in src:
        dst.write(block)
        n += len(block)
    return n
Write data from `src` into `dst`.

    Args:
        src (iterable): iterable that yields blocks of data to write
        dst (file-like object): file-like object that must support
            .write(block)

    Returns:
        number of bytes written to `dst`