def METHOD_NAME():
    @pipeline_def(enable_conditionals=True, num_threads=4, batch_size=8, device_id=0)
    def pipeline():
        pred = fn.external_source(source=lambda x: np.array(x.idx_in_batch % 2), batch=False)
        if pred:
            out = {'out': np.array(2), 'mismatched': np.array(9999)}
        else:
            out = {'out': np.array(1)}
        return out
    with assert_raises(
            ValueError, glob=("*Divergent data found in different branches of `if/else` control"
                              " flow statement. Variables in all code paths are merged into common"
                              " output batches. The values assigned to a given variable need to"
                              " have the same nesting structure in every code path"
                              " (both `if` branches).*"
                              "*The two structures don't have the same nested structure*"
                              "*The two dictionaries don't have the same set of keys."
                              " First structure has keys type=list str=*'out', 'mismatched'*,"
                              " while second structure has keys type=list str=*'out'*")):
        _ = pipeline()