input: from typing import Dict
  
  def get_customer_info(customer_db: Dict[str, str], name: str) -> str:
      """
      Given a dictionary representing a customer database and a customer name, 
      return the customer's information if found, or a default message if not.
      
      >>> get_customer_info({'John Doe': '123 Main St', 'Jane Smith': '456 Oak Ave'}, 'John Doe')
      '123 Main St'
      >>> get_customer_info({'John Doe': '123 Main St', 'Jane Smith': '456 Oak Ave'}, 'Alice')
      'Customer not found'
      """
      return customer_db.get(name, 'Customer not found')
output:     return customer_db.get(name, 'Customer not found')