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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 edges(self, tail_head_iter):
 """Create a bunch of edges. Args: tail_head_iter: Iterable of ``(tail_name, head_name)`` pairs. """

        edge = self._edge_plain
        quote = self._quote_edge
        lines = (edge % (quote(t), quote(h)) for t, h in tail_head_iter)
        self.body.extend(lines)