@@ -0,0 +1,782 @@
+#!/usr/bin/env python%0A%0Afrom messages import Messages%0A%0A%0Aclass Check:%0A%0A    checkables = %7B%7D%0A%0A    @classmethod%0A    def add_checkable(cls, checkable, method):%0A        if checkable in cls.checkables:%0A            raise KeyError(Messages.get_error(%22CHECKABLE_ALREADY_IN_CHECKABLES%22).format(checkable))%0A%0A        cls.checkables%5Bcheckable%5D = method%0A%0A    @classmethod%0A    def get_checkables(cls):%0A        return cls.checkables%0A%0A    @classmethod%0A    def check_prerequisite_of(cls, case):%0A        if case in cls.checkables:%0A            return cls.checkables%5Bcase%5D(%22check%22)%0A%0A        return False%0A%0A    @classmethod%0A    def check_prerequisites(cls):%0A        for case in cls.get_checkables():%0A            if cls.check_prerequisite_of(case) is False:%0A                return False%0A%0A        return True%0A

Add check.py helper script