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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 job_from_resource(self, resource):
 """Detect correct job type from resource and instantiate. :type resource: dict :param resource: one job resource from API response :rtype: One of: :class:`google.cloud.bigquery.job.LoadJob`, :class:`google.cloud.bigquery.job.CopyJob`, :class:`google.cloud.bigquery.job.ExtractJob`, or :class:`google.cloud.bigquery.job.QueryJob` :returns: the job instance, constructed via the resource """

        config = resource.get("configuration", {})
        if "load" in config:
            return job.LoadJob.from_api_repr(resource, self)
        elif "copy" in config:
            return job.CopyJob.from_api_repr(resource, self)
        elif "extract" in config:
            return job.ExtractJob.from_api_repr(resource, self)
        elif "query" in config:
            return job.QueryJob.from_api_repr(resource, self)
        return job.UnknownJob.from_api_repr(resource, self)