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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 _MakeExecutable(self, metadata_script):
 """Add executable permissions to a file. Args: metadata_script: string, the path to the executable file. """

    mode = os.stat(metadata_script).st_mode
    os.chmod(metadata_script, mode | stat.S_IEXEC)