input: Write a function to translate a given text from English to French using the `googletrans` module. The function should return the translated text. If the input text is empty, the function should return an empty string.
  assert translate_text("Hello, this is a sample text to translate.") == "Bonjour, ceci est un exemple de texte à traduire."
  assert translate_text("Good morning!") == "Bonjour !"
  assert translate_text("") == ""
output: from googletrans import Translator
  
  def translate_text(text):
      if not text:
          return ""
      translator = Translator()
      translation = translator.translate(text, src='en', dest='fr')
      return translation.text