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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 set_item(key,value):

 """Write JSON content from value argument to cached file and return"""

    CACHED_KEY_FILE = os.path.join(CURRENT_DIR, key)

    open(CACHED_KEY_FILE, "wb").write(json.dumps({"_": value}).encode('UTF-8'))

    return value