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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_all_build_configs_by_labels(self, label_selectors):
 """ Returns all builds matching a given set of label selectors. It is up to the calling function to filter the results. """

        labels = ['%s=%s' % (field, value) for field, value in label_selectors]
        labels = ','.join(labels)
        url = self._build_url("buildconfigs/", labelSelector=labels)
        return self._get(url).json()['items']