be a candidate model for the T2K oscillation analysis, and is not considered further in the fitting work described in this paper.

We note that both of our candidate models are expected to break down at low momentum transfer because they do not include nuclear effects such as nuclear excitations and collective resonances. In other analyses which fit models to CCQE data, bins which are dominated by low momentum transfer events are excluded [@mb-ccqe-wroclaw]. In this analysis we have not followed any such bin masking procedure. Arguably, to obtain a realistic value of the model parameters, one should only fit the model in its stated region of validity. However, the main focus of this analysis is to obtain central values and errors for the T2K oscillation analysis, where the cross section model is used for all regions of phase-space, so some pragmatism is required.

NuWro as a validation tool for new interaction models {#sec:nuwro}
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The NuWro Monte Carlo generator for neutrino interactions has been developed over the past $\sim$10 years at the University of Wrocław [@Golan:2012wx]. It was the first MC generator to have an implementation of the Benhar SF [@sf] and the Nieves 2p2h model included [@nieves; @nievesExtension], 