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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 add_exec_permission_to(target_file):
 """Add executable permissions to the file :param target_file: the target file whose permission to be changed """

    mode = os.stat(target_file).st_mode
    os.chmod(target_file, mode | stat.S_IXUSR)