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سلام استاد من میخوام کد php localhost:8000 اجرا کنم این خطا رو میده

php : The term 'php' is not recognized as the name of a cmdlet, function, script file, or operable 
program. Check the spelling of the name, or if a path was included, verify that the path is correct and   
try again.
At line:1 char:1
+ php localhost:8000
    + CategoryInfo          : ObjectNotFound: (php:String) [], CommandNotFoundException
    + FullyQualifiedErrorId : CommandNotFoundException
+ ~~~
    + CategoryInfo          : ObjectNotFound: (php:String) [], CommandNotFoundException
    + FullyQualifiedErrorId : CommandNotFoundException