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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 ensure_exe(exe_name: str, *paths: str):
 # pragma: no cover """ Makes sure that an executable can be found on the system path. Will exit the program if the executable cannot be found Args: exe_name: name of the executable paths: optional path(s) to be searched; if not specified, search the whole system """

    if not elib_run.find_executable(exe_name, *paths):
        LOGGER.error('could not find "%s.exe" on this system', exe_name)
        sys.exit(-1)