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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_node_at_path(query_path, context):
 """Return the SqlNode associated with the query path."""

    if query_path not in context.query_path_to_node:
        raise AssertionError(
            u'Unable to find SqlNode for query path {} with context {}.'.format(
                query_path, context))
    node = context.query_path_to_node[query_path]
    return node