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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 _pretty_alignment_out_file_name(self):
 """Checks file name is set for pretty alignment output. Returns absolute path."""

        if self.Parameters['-E'].isOn():
            pretty_alignment = self._absolute(str(self.Parameters['-E'].Value))
        else:
            raise ValueError(
                "No pretty-=alignment (flag -E) output path specified")
        return pretty_alignment