Run 'show | compare' for set commands.

    @param ctx: The click context paramter, for receiving the object dictionary
              | being manipulated by other previous functions. Needed by any
              | function with the @click.pass_context decorator.
    @type ctx: click.Context
    @param commands: The Junos set commands that will be put into a candidate
                   | configuration and used to create the 'show | compare'
                   | against the running configuration. much like the commands
                   | parameter for the commit() function, this can be one of
                   | three things: a string containing a single command, a
                   | string containing a comma separated list of commands, or
                   | a string containing a filepath location for a file with
                   | commands on each line.
    @type commands: str

    @returns: None. Functions part of click relating to the command group
            | 'main' do not return anything. Click handles passing context
            | between the functions and maintaing command order and chaining.

def compare(ctx, commands):
    """ Run 'show | compare' for set commands.

    @param ctx: The click context paramter, for receiving the object dictionary
              | being manipulated by other previous functions. Needed by any
              | function with the @click.pass_context decorator.
    @type ctx: click.Context
    @param commands: The Junos set commands that will be put into a candidate
                   | configuration and used to create the 'show | compare'
                   | against the running configuration. much like the commands
                   | parameter for the commit() function, this can be one of
                   | three things: a string containing a single command, a
                   | string containing a comma separated list of commands, or
                   | a string containing a filepath location for a file with
                   | commands on each line.
    @type commands: str

    @returns: None. Functions part of click relating to the command group
            | 'main' do not return anything. Click handles passing context
            | between the functions and maintaing command order and chaining.
    """
    mp_pool = multiprocessing.Pool(multiprocessing.cpu_count() * 2)
    for ip in ctx.obj['hosts']:
        mp_pool.apply_async(wrap.open_connection, args=(ip,
                            ctx.obj['conn']['username'],
                            ctx.obj['conn']['password'],
                            wrap.compare, [commands],
                            ctx.obj['out'],
                            ctx.obj['conn']['connect_timeout'],
                            ctx.obj['conn']['session_timeout'],
                            ctx.obj['conn']['port']), callback=write_out)
    mp_pool.close()
    mp_pool.join()