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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 raw_field_definition_proxy_post_save(sender, instance, raw, **kwargs):
 """ When proxy field definitions are loaded from a fixture they're not passing through the `field_definition_post_save` signal. Make sure they are. """

    if raw:
        model_class = instance.content_type.model_class()
        opts = model_class._meta
        if opts.proxy and opts.concrete_model is sender:
            field_definition_post_save(
                sender=model_class, instance=instance.type_cast(), raw=raw,
                **kwargs
            )