input: Write a function to create a Python class with the given attributes and functions. The class should have attributes name (string), age (integer), and email address (string) and a function toString() that returns a string with the formatted attributes.
  assert Person("John Doe", 25, "john@example.com").toString() == "Name: John Doe, Age: 25, Email: john@example.com"
  assert Person("Jane Smith", 30, "jane@example.com").toString() == "Name: Jane Smith, Age: 30, Email: jane@example.com"
  assert Person("", 0, "").toString() == "Name: , Age: 0, Email: "
  assert Person("Alice", -1, "alice@example.com").toString() == "Name: Alice, Age: -1, Email: alice@example.com"
output: class Person:
      def __init__(self, name, age, email):
          self.name = name
          self.age = age
          self.email = email
      
      def toString(self):
          return f"Name: {self.name}, Age: {self.age}, Email: {self.email}"