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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 body(self, **kwargs):
 """ Return the plain and html versions of our contents. Return: tuple Exceptions: None """

        text_content, html_content = None, None
        if self.plain:
            text_content = mold.cast(self.plain, **kwargs)
        if self.html:
            html_content = mold.cast(self.html, **kwargs)
        return text_content, html_content