Equal Rational Numbers LeetCode solution in Python

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class Solution:
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    import typing
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    def isRationalEqual(self, s: str, t: str) -> bool:
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        # intuition:
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        # write each numbes as fraction: num / den
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        # then compare the two fractions.
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        num1, den1 = self.toFraction(s)
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        num2, den2 = self.toFraction(t)
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        return den1 * num2 == den2 * num1
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    def toFraction(self, s: str) -> typing.Tuple[int, int]:
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        if "." not in s:
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            return int(s), 1
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        intp, frac = s.split(".")
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        # decimal dot, but no repeating part:
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        # xyz.abc = xyzabc / 1000
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        if "(" not in frac:
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            ifrac = int(frac) if len(frac) > 0 else 0
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            num = int(intp) * (10 ** len(frac)) + ifrac
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            den = 10 ** len(frac)
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            return num, den
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        # this is for cases like a.b(c)
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        # let n = a.b(c)
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        # then, 10^(len(b+c)) * n = abc.(c)
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        # and 10^(len(b)) * n = ab.(c)
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        # subtract the two, and solve for n:
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        # n = (abc - ab) / (10^len(b + c) - 10^len(b))
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        frac, repfrac = frac.split("(")
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        repfrac = repfrac[:-1]
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        iintp = int(intp)
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        ifrac = int(frac) if len(frac) > 0 else 0
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        irep = int(repfrac)
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        return (
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            (iintp * (10 ** (len(frac + repfrac))) + ifrac * 10 ** len(repfrac) + irep)
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            - (iintp * 10 ** len(frac) + ifrac),
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            (10 ** len(frac + repfrac) - 10 ** len(frac)),
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        )