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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 _setup(self):
 """ Setup the environment on disk using virtualenv. Then, all of the requirements are installed into it using `pip install`. """

        log.info("Creating virtualenv for {0}".format(self.name))
        util.check_call([
            sys.executable,
            "-mvirtualenv",
            '--no-site-packages',
            "-p",
            self._executable,
            self._path])

        log.info("Installing requirements for {0}".format(self.name))
        self._install_requirements()