input: Write a function to verify if a Python class with given attributes and functions, named 'Person', correctly formats and returns a string with the attributes as specified. The class should have attributes 'name', 'age', and 'email', and a 'toString' function that returns a formatted string with these attributes.
  assert Person("John Doe", 30, "john.doe@example.com").toString() == "Name: John Doe, Age: 30, Email: john.doe@example.com"
  assert Person("Jane Smith", 25, "jane.smith@example.com").toString() == "Name: Jane Smith, Age: 25, Email: jane.smith@example.com"
  assert Person("Alex Johnson", 22, "alex.johnson@example.com").toString() == "Name: Alex Johnson, Age: 22, Email: alex.johnson@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}"