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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def foreign_field_func(field_name, short_description=None, admin_order_field=None):
 """ Allow to use ForeignKey field attributes at list_display in a simple way. Example: from misc.admin import foreign_field_func as ff class SongAdmin(admin.ModelAdmin):
 list_display = ['name', 'time', 'artist', 'album', ff('track__num', "Track number"), ff('album__total_tracks')] """
  
    def accessor(obj): 
        val = obj 
        for part in field_name.split('__'): 
            val = getattr(val, part) 
        return val 
    
    if short_description: 
        accessor.short_description = short_description 
    else: 
        accessor.__name__ = field_name 
    if admin_order_field: 
        accessor.admin_order_field = admin_order_field 
    else: 
        accessor.admin_order_field  = (field_name,) 
    
    return accessor