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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 pip_install(self, reqs):
 """Install dependencies into this env by calling pip in a subprocess"""

        if not reqs:
            return
        log.info('Calling pip to install %s', reqs)
        check_call([
            sys.executable, '-m', 'pip', 'install', '--ignore-installed',
            '--prefix', self.path] + list(reqs))