def METHOD_NAME(adata_reference: AnnData, mdata_query: MuData, adata_query: AnnData, reference_proteins_key: str, query_proteins_key: str) -> AnnData:
    """Make sure that proteins are located in the same .obsm slot in reference and query. Pad query proteins with zeros if they are absent"""
    proteins_reference = adata_reference.obsm[reference_proteins_key]
    # If query has no protein data, put matrix of zeros 
    if not query_proteins_key or query_proteins_key not in mdata_query.mod:
        adata_query.obsm[reference_proteins_key] = np.zeros((adata_query.n_obs, proteins_reference.shape[1]))
    else:
        # Make sure that proteins expression has the same key in query and reference
        adata_query.obsm[reference_proteins_key] = adata_query.obsm[query_proteins_key]
    return adata_query