input: Write a python function to summarize a text into a limited number of sentences.
  assert summarize("This is a test. This test is only a test. This test is the best test. Keep testing. This is the end of the test.", limit=2) == "This is a test.\nThis test is the best test.\n"
  assert summarize("Python is a powerful programming language. It is widely used in various fields. Python is easy to learn. It has a large community. Python supports multiple paradigms.", limit=3) == "Python is a powerful programming language.\nPython is easy to learn.\nIt has a large community.\n"
  assert summarize("Artificial Intelligence is the future. AI is transforming industries. Machine learning is a subset of AI. AI can improve efficiency. Ethical considerations are important in AI development.", limit=2) == "Artificial Intelligence is the future.\nAI is transforming industries.\n"
output: def summarize(text, limit):
      sentences = text.split('. ')
      return '\n'.join(sentences[:limit]) + '\n'