code: def bench_nsmallest(benchmark, dataframe, num_cols_to_sort, n):
      by = list(dataframe.columns[:num_cols_to_sort])
      benchmark(dataframe.nsmallest, n, by)
  
imports: import string
  import numpy
  import pytest
  import pytest_cases
  from config import cudf, cupy
  from utils import benchmark_with_object
label_desc: Use image node_id 15 for calling a global function with example usage: bench_nsmallest(benchmark, dataframe, num_cols_to_sort, n) without return types