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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_full_layer_uri(full_layer_uri_string):
 """Decode the full layer URI. :param full_layer_uri_string: The full URI provided by our helper. :type full_layer_uri_string: basestring :return: A tuple with the QGIS URI and the provider key. :rtype: tuple """

    if not full_layer_uri_string:
        return None, None

    split = full_layer_uri_string.split('|qgis_provider=')
    if len(split) == 1:
        return split[0], None
    else:
        return split