input: 
  from typing import List
  
  
  def linearSearch(search_item: str) -> int:
      """
      Searches for an item in a predefined array using a linear search algorithm.
      Returns the position of the item if found, otherwise returns -1.
  
      >>> linearSearch('hospital')
      1
      >>> linearSearch('mall')
      3
      >>> linearSearch('library')
      -1
      """
      array = ['school', 'hospital', 'bookstore', 'mall', 'theatre']
      for i in range(len(array)):
          if array[i] == search_item:
              return i
      return -1
  
output:     array = ['school', 'hospital', 'bookstore', 'mall', 'theatre']
      for i in range(len(array)):
          if array[i] == search_item:
              return i
      return -1