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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 prepare_context(pipeline, context_in_string, context):
 """Prepare context for pipeline run. Args: pipeline: dict. Dictionary representing the pipeline. context_in_string: string. Argument string used to initialize context. context: pypyr.context.Context. Merge any new context generated from context_in_string into this context instance. Returns: None. The context instance to use for the pipeline run is contained in the context arg, it's not passed back as a function return. """

    logger.debug("starting")

    parsed_context = get_parsed_context(
        pipeline=pipeline,
        context_in_string=context_in_string)

    context.update(parsed_context)

    logger.debug("done")