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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 _float(self, string):
 """Convert string to float Take care of numbers in exponential format """

        string = self._denoise(string)
        exp_match = re.match(r'^[-.\d]+x10-(\d)$', string)
        if exp_match:
            exp = int(exp_match.groups()[0])
            fac = 10 ** -exp
            string = string.replace('x10-{}'.format(exp), '')
        else:
            fac = 1

        return fac * float(string)