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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 validate(self, email, **kwargs):
 """Check to see if this is a valid email address."""

        email = stringify(email)
        if email is None:
            return
        if not self.EMAIL_REGEX.match(email):
            return False
        mailbox, domain = email.rsplit('@', 1)
        return self.domains.validate(domain, **kwargs)