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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 _fmt_exp(cls, x, **kw):
 """Exponential formatting class-method. - x parameter is ignored. Instead kw-argument f being x float-converted will be used. - precision will be taken from `n` kw-argument. """

        n = kw.get('n')
        return '%.*e' % (n, cls._to_float(x))