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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 decode_jwt(encoded_token):
 """ Returns the decoded token from an encoded one. This does all the checks to insure that the decoded token is valid before returning it. """

    secret = config.decode_key
    algorithm = config.algorithm
    audience = config.audience
    return jwt.decode(encoded_token, secret, algorithms=[algorithm], audience=audience)