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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 _invoke(self, *params):
 		""" 		Invoke self.exe as a subprocess 		"""

		cmd = [self.exe] + list(params)
		proc = subprocess.Popen(
			cmd, stdout=subprocess.PIPE,
			stderr=subprocess.PIPE, cwd=self.location, env=self.env)
		stdout, stderr = proc.communicate()
		if not proc.returncode == 0:
			raise RuntimeError(stderr.strip() or stdout.strip())
		return stdout.decode('utf-8')