input: def generate_sample_data() -> str:
      """ Generate sample data for a web application using Python's faker library. 
      The output should contain three columns of data: name, email, and age.
  
      >>> generate_sample_data()
      'John Doe john.doe@example.com 32\nAlice Johnson alice.johnson@example.com 45\n...(and so on for 10 entries)'
      """
output:     from faker import Faker
      fake = Faker()
      data = []
      for _ in range(10):
          name = fake.name()
          email = fake.email()
          age = fake.random_int(min=18, max=65)
          data.append(f"{name} {email} {age}")
      return "\n".join(data)