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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 _significand(self):
 """Return the significand of self, as a BigFloat. If self is a nonzero finite number, return a BigFloat m with the same precision as self, such that 0.5 <= m < 1. and self = +/-m * 2**e for some exponent e. If self is zero, infinity or nan, return a copy of self with the sign set to 0. """

        m = self.copy()
        if self and is_finite(self):
            mpfr.mpfr_set_exp(m, 0)
        mpfr.mpfr_setsign(m, m, False, ROUND_TIES_TO_EVEN)
        return m