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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 leaf(self, node, elem, module, path):
 """Create a sample leaf element."""

        if node.i_default is None:
            nel, newm, path = self.sample_element(node, elem, module, path)
            if path is None:
                return
            if self.annots:
                nel.append(etree.Comment(
                    " type: %s " % node.search_one("type").arg))
        elif self.defaults:
            nel, newm, path = self.sample_element(node, elem, module, path)
            if path is None:
                return
            nel.text = str(node.i_default_str)