input: Write a function in Python to search for a given word in a large document. The function should return the line number of the document where the word is found.
  
  ### Example Input:
  largeDocument = 'This is the first line of the document.\nThis is the second line of the document.\nThis is the third line of the document.';
  word = 'second'
  
  ### Example Output:
  
  def findWord(document, word):
   lines = document.split('\n')
   line_number = -1
   for i, line in enumerate(lines):
   if word in line:
   line_number = (i + 1)
   break
   return line_number
  
  findWord(largeDocument, word) # 2
  
  
  ---
  
  **执行问题:**
  
  Verify that the function correctly returns the line number where the specified word is found in a large document. If the word is not found, ensure the function returns -1.
  
  **验证示例:**
  
  assert findWord('This is the first line.\nSecond line contains word.\nThird line is here.', 'word') == 2
  assert findWord('Multiple lines here.\nsearch term is absent.\nfind me if you can.', 'find') == 3
  assert findWord('Single line document.\nNo other lines.', 'line') == -1
  assert findWord('', 'search_term') == -1
  # 验证通过或失败的临时标记
  passed = False
  try:
   if findWord('This is the first line.\nSecond line contains word.\nThird line is here.', 'word') == 2:
   print("First test passed.")
   passed = True
  except AssertionError:
   passed = False
  assert passed, "The first test failed."
  
  passed = False
  try:
   if findWord('Multiple lines here.\nsearch term is absent.\nfind me if you can.', 'find') == 3:
   print("Second test passed.")
   passed = True
  except AssertionError:
   passed = False
  assert passed, "The second test failed."
  
  passed = False
  try:
   if findWord('Single line document.\nNo other lines.', 'line') == -1:
   print("Third test passed.")
   passed = True
  except AssertionError:
   passed = False
  assert passed, "The third test failed."
  
  passed = False
  try:
   if findWord('', 'search_term') == -1:
   print("Fourth test passed.")
   passed = True
  except AssertionError:
   passed = False
  assert passed, "The fourth test failed."
  
  确保上述测试示例逐一验证函数的准确性，并修订函数bug（如果在运行测试时出现），以便函数在返回所需的行号时具有全面的正确性。
  
  期望通过对该问题的执行和细化，形成实际有效的函数验证示例执行函数部分的代码。
output: def findWord(document, word):
      lines = document.split('\n')
      line_number = -1
      for i, line in enumerate(lines):
          if word in line:
              line_number = (i + 1)
              break
      return line_number