class_docstr: A flow where Metaflow prints 'Hi'.
  
  Run this flow to validate that Metaflow is installed correctly.
class_docstr_tok: ["A","flow","where","Metaflow","prints","'Hi","'",".","Run","this","flow","to","validate","that","Metaflow","is","installed","correctly","."]
docstr: This is the 'start' step. All flows must have a step named 'start' that
  is the first step in the flow.
docstr_tok: ["This","is","the","'start","'","step",".","All","flows","must","have","a","step","named","'start","'","that","is","the","first","step","in","the","flow","."]
code: def start(self):
      """
      This is the 'start' step. All flows must have a step named 'start' that
      is the first step in the flow.
  
      """
      print("HelloFlow is starting.")
      self.next(self.hello)
  
imports: from metaflow import FlowSpec, step
label_desc: Use image node_id 1 for calling the HelloFlow obj's underlying member method code with example usage: obj.start() without return types