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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 get_item(key):

 """Return content in cached file in JSON format"""

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

    try:
        return json.loads(open(CACHED_KEY_FILE, "rb").read().decode('UTF-8'))["_"]
    except (IOError, ValueError):
        return None