code: def indexof(coll, item, start=0, default=None):
      
      if item in coll[start:]:
          return list(coll).index(item, start)
      else:
          return default
docs: Return the index of the item in the collection
  
      :param coll: iterable
      :param item: scalar
      :param start: (optional) The start index
      :default: The default value of the index if the item is not in the collection
  
      :returns: idx -- The index of the item in the collection
  
      >>> monties = ['Eric', 'John', 'Terry', 'Terry', 'Graham', 'Mickael']
      >>> indexof(monties, 'Terry')
      2
  
      >>> indexof(monties, 'Terry', start=3)
      3
  
      >>> indexof(monties, 'Terry', start=4) is None
      True