class_docstr: Gather the input from model parallel region and concatenate.
  
  Args:
      input_: input matrix.
      parallel_mode: parallel mode.
      dim: dimension
class_docstr_tok: ["Gather","the","input","from","model","parallel","region","and","concatenate",".","Args",":","input_",":","input","matrix",".","parallel_mode",":","parallel","mode",".","dim",":","dimension"]
code: def symbolic(graph, input_):
      return _gather(input_)
  
imports: import torch
  import torch.distributed
  from colossalai.legacy.core import global_context
  from colossalai.legacy.global_variables import tensor_parallel_env
  from ..utils import divide
label_desc: Use image node_id 1 for calling the _GatherForwardSplitBackward obj's underlying member method code with example usage: obj.symbolic(graph, input_) and returns: _gather