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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 _append_params(oauth_params, params):
 """Append OAuth params to an existing set of parameters. Both params and oauth_params is must be lists of 2-tuples. Per `section 3.5.2`_ and `3.5.3`_ of the spec. .. _`section 3.5.2`: https://tools.ietf.org/html/rfc5849#section-3.5.2 .. _`3.5.3`: https://tools.ietf.org/html/rfc5849#section-3.5.3 """

    merged = list(params)
    merged.extend(oauth_params)
    # The request URI / entity-body MAY include other request-specific
    # parameters, in which case, the protocol parameters SHOULD be appended
    # following the request-specific parameters, properly separated by an "&"
    # character (ASCII code 38)
    merged.sort(key=lambda i: i[0].startswith('oauth_'))
    return merged