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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_channel_node_from_json(json_tree):
 """ Build `ChannelNode` from json data provided in `json_tree`. """

    channel = ChannelNode(
        title=json_tree['title'],
        description=json_tree['description'],
        source_domain=json_tree['source_domain'],
        source_id=json_tree['source_id'],
        language=json_tree['language'],
        thumbnail=json_tree.get('thumbnail', None),
    )
    return channel