Searches "django.core" and the apps in settings.INSTALLED_APPS to find the
    named command class, optionally skipping packages or a particular command
    class. Gathers the command's default options and returns the command and
    options dictionary as a two-tuple: (command, options). Returns (None, {})
    if the command class could not be found.

def get_command_and_defaults(name, exclude_packages=None, exclude_command_class=None):
    """
    Searches "django.core" and the apps in settings.INSTALLED_APPS to find the
    named command class, optionally skipping packages or a particular command
    class. Gathers the command's default options and returns the command and
    options dictionary as a two-tuple: (command, options). Returns (None, {})
    if the command class could not be found.
    
    """
    command = get_command_class(name,
        exclude_packages=exclude_packages,
        exclude_command_class=exclude_command_class)
    defaults = {}
    if command is not None:
        command = command()
        defaults = command.get_option_defaults() \
            if isinstance(command, Command) \
            else get_option_defaults(command)
    return (command, defaults)