class_docstr: Concatenates all the pipelins
  
  Examples:
      p1 = towhee.pipe.input('url').map('url', 'image', ops.image_decode.cv2())
      p2 = p1.map('image', 'vec1', ops.embedding.timm(model='resnet50'))
      p3 = p1.map('image', 'vec2', ops.embedding.timm(model='resnet50'))
      p1.concat(p2, p3).map(('vec1', 'vec2'), 'vec', ops.numpy_util.merge()).output('vec')
class_docstr_tok: ["Concatenates","all","the","pipelins","Examples",":","p1","=","towhee.pipe.input","(","'url","'",")",".map","(","'url","'",",","'image","'",",","ops.image_decode.cv2","(",")",")","p2","=","p1.map","(","'image","'",",","'vec1","'",",","ops.embedding.timm","(","model='resnet50","'",")",")","p3","=","p1.map","(","'image","'",",","'vec2","'",",","ops.embedding.timm","(","model='resnet50","'",")",")","p1.concat","(","p2",",","p3",")",".map","(","(","'vec1","'",",","'vec2","'",")",",","'vec","'",",","ops.numpy_util.merge","(",")",")",".output","(","'vec","'",")"]
code: def initialize(self) -> bool:
      for q in self._in_ques:
          q.max_size = 0
  
      q_nums = len(self._in_ques)
      all_cols = []
      self.cols_every_que = []
      while q_nums > 0:
          cols = []
          schema = self._in_ques[q_nums - 1].schema
          for col in schema:
              if col not in all_cols:
                  cols.append(col)
          self.cols_every_que.append(cols)
          all_cols.extend(cols)
          q_nums -= 1
      self.cols_every_que.reverse()
      return True
  
imports: from .node import Node
  from towhee.runtime.time_profiler import Event
label_desc: Use image node_id 1 for calling the Concat obj's underlying member method code with example usage: obj.initialize() and returns: True