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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def add_email_grant(self, permission, email_address, headers=None):
 """ Convenience method that provides a quick way to add an email grant to a key. This method retrieves the current ACL, creates a new grant based on the parameters passed in, adds that grant to the ACL and then PUT's the new ACL back to S3. :type permission: string :param permission: The permission being granted. Should be one of: (READ, WRITE, READ_ACP, WRITE_ACP, FULL_CONTROL). :type email_address: string :param email_address: The email address associated with the AWS account your are granting the permission to. :type recursive: boolean :param recursive: A boolean value to controls whether the command will apply the grant to all keys within the bucket or not. The default value is False. By passing a True value, the call will iterate through all keys in the bucket and apply the same grant to each key. CAUTION: If you have a lot of keys, this could take a long time! """

        policy = self.get_acl(headers=headers)
        policy.acl.add_email_grant(permission, email_address)
        self.set_acl(policy, headers=headers)