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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 insert_completions(self, e):
 # (M-*)
 u"""Insert all completions of the text before point that would have
 been generated by possible-completions."""

        completions = self._get_completions()
        b = self.begidx
        e = self.endidx
        for comp in completions:
            rep = [ c for c in comp ]
            rep.append(' ')
            self.l_buffer[b:e] = rep
            b += len(rep)
            e = b
        self.line_cursor = b    
        self.finalize()