code: def time_concatenate_ax0(self, size, narrays, ndtype):
      np.concatenate(self.xarg, axis=0)
  
imports: from .common import Benchmark, get_squares_, TYPES1, DLPACK_TYPES
  import numpy
  from collections import deque
label_desc: Use image node_id 2 for calling the ConcatenateStackArrays obj's underlying member method code with example usage: obj.time_concatenate_ax0(size, narrays, ndtype) without return types