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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 choice_install(self):
 """Download, build and install package """

        pkg_security([self.name])
        if not find_package(self.prgnam, self.meta.pkg_path):
            self.build()
            self.install()
            delete(self.build_folder)
            raise SystemExit()
        else:
            self.msg.template(78)
            self.msg.pkg_found(self.prgnam)
            self.msg.template(78)
            raise SystemExit()