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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 execute_executable(nova_args, env_vars):
 """ Executes the executable given by the user. Hey, I know this method has a silly name, but I write the code here and I'm silly. """

    process = subprocess.Popen(nova_args,
                               stdout=sys.stdout,
                               stderr=subprocess.PIPE,
                               env=env_vars)
    process.wait()
    return process