input: Write a python function to submit a form using the requests library.
  assert submit_form('http://example.com/form-submit', {'name': 'John Doe', 'email': 'john@example.com'}) == 'Form submitted successfully!'
  assert submit_form('http://example.com/form-submit', {'name': 'Jane Doe', 'email': 'jane@example.com'}) == 'Form submitted successfully!'
  assert submit_form('http://example.com/form-submit', {'name': 'Alice', 'email': 'alice@example.com'}) == 'Form submitted successfully!'
output: def submit_form(url, data):
      import requests
      response = requests.post(url, data=data)
      if response.status_code == 200:
          return 'Form submitted successfully!'
      else:
          return 'Failed to submit form'