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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 compute_token(random_token, config):
 """Compute a hash of the given token with a preconfigured secret. :param random_token: random token :type random_token: str :return: hashed token :rtype: str """

    secure_token = config[TOKEN_SERVICE_SECURITY_CONFIG]
    sha1hash = hashlib.sha1()
    sha1hash.update(random_token + secure_token)
    return sha1hash.hexdigest().upper()