<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _markup(p_todo, p_focus):
 """ Returns an attribute spec for the colors that correspond to the given todo item. """

    pri = p_todo.priority()
    pri = 'pri_' + pri if pri else PaletteItem.DEFAULT

    if not p_focus:
        attr_dict = {None: pri}
    else:
        # use '_focus' palette entries instead of standard ones
        attr_dict = {None: pri + '_focus'}
        attr_dict[PaletteItem.PROJECT] = PaletteItem.PROJECT_FOCUS
        attr_dict[PaletteItem.CONTEXT] = PaletteItem.CONTEXT_FOCUS
        attr_dict[PaletteItem.METADATA] = PaletteItem.METADATA_FOCUS
        attr_dict[PaletteItem.LINK] = PaletteItem.LINK_FOCUS

    return attr_dict