input: Write a python function to search for a string in a list of strings and return True if found.
  assert search_string('python', ['java', 'javascript', 'python', 'ruby']) == True
  assert search_string('c++', ['java', 'javascript', 'python', 'ruby']) == False
  assert search_string('ruby', ['java', 'javascript', 'python', 'ruby']) == True
output: def search_string(target, lst):
      return target in lst