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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 send_email_message(self, recipient, subject, html_message, text_message, sender_email, sender_name):
 """ Send email message via Flask-Sendmail. Args: recipient: Email address or tuple of (Name, Email-address). subject: Subject line. html_message: The message body in HTML. text_message: The message body in plain text. """


        if not current_app.testing:  # pragma: no cover

            # Prepare email message
            from flask_sendmail import Message
            message = Message(
                subject,
                recipients=[recipient],
                html=html_message,
                body=text_message)

            # Send email message
            self.mail.send(message)