input: Write a python function to sort a list of keywords alphabetically.
  assert sort_keywords(["machine learning model", "build machine learning model", "Python", "machine learning", "machine learning Python", "model building machine learning", "build model Python"]) == ["Python", "build machine learning model", "build model Python", "machine learning", "machine learning Python", "machine learning model", "model building machine learning"]
  assert sort_keywords(["apple", "banana", "cherry", "date"]) == ["apple", "banana", "cherry", "date"]
  assert sort_keywords(["zebra", "monkey", "aardvark", "elephant"]) == ["aardvark", "elephant", "monkey", "zebra"]
output: def sort_keywords(keywords):
      return sorted(keywords)