This property method takes the non-empty string self.__expr, an arithmetic expression in infix notation, calls _getPostfix(expr) to obtain the postfix expression of self.__expr and then uses a Stack (as described in the Stack video lecture from Module 5) to evaluate the obtained postfix expression. All values returned by calculator should be float if expr is a correct expression, otherwise it must return None. - Do not use exec or eval function. You will not receive credit if your program uses any of the two functions anywhere - Note that you can write the code for this method without having an implementation for _getPostfix. The process for calculate is explained during the stack video lectures

4. a1. vince owns a television repair shop that is insured undera commercial package policy. the policy includes thebuilding and personal property coverage form and thecauses-of-loss broad form. the declarations page indicatesthat coverage applies to both the building and the namedinsured's business property. explain whether or not thefollowing losses would be covered under his policy.a. a fire occurs on the premises, and the building isbadly damaged.b. a burglar steals some money and securities from anunlocked safe.c. a business computer is damaged by vandals whobreak into the shop after business hours.d. a tornado touches down near the store. several tel-evision sets of customers in the shop for repair aredamaged in the storm.til