code: def head_split(self, x):
      reshaped = x.reshape(
          x.shape[:-1] + (self.n_head // self.mp_num, self.d_head)
      )
      reshaped = reshaped.reshape(x.shape[:-2] + (-1,) + x.shape[-1:])
  
      # return reshaped
      return maybe_shard(reshaped, P("dp", None, "mp", None))
  
imports: import haiku
  import jax
  import jax.numpy
  import numpy
  from einops import rearrange, repeat
  from mesh_transformer.util import f_psum, g_psum, maybe_shard, head_print
  from jax.experimental import PartitionSpec
  from jax.experimental.maps import thread_resources
label_desc: Use image node_id 3 for calling the TransformerLayerShardV2 obj's underlying member method code with example usage: obj.head_split(x) and returns: maybe_shard