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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_group_email_grant(self, permission, email_address, headers=None):
 """ Convenience method that provides a quick way to add an email group 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 GS. :type permission: string :param permission: The permission being granted. Should be one of: READ|FULL_CONTROL See http://code.google.com/apis/storage/docs/developer-guide.html#authorization for more details on permissions. :type email_address: string :param email_address: The email address associated with the Google Group to which you are granting the permission. """

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