Find in Mountain Array LeetCode solution in Python

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# """
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# This is MountainArray's API interface.
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# You should not implement it, or speculate about its implementation
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# """
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# class MountainArray:
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#    def get(self, index: int) -> int:
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#    def length(self) -> int:
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class Solution:
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    def findInMountainArray(self, target: int, mountain_arr: "MountainArray") -> int:
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        min_index = -1
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        peak = self.findpeak(mountain_arr)
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        min_index = self.binary_search(0, peak, mountain_arr, target, 1)
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        if min_index == -1:
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            min_index = self.binary_search(
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                peak + 1, mountain_arr.length() - 1, mountain_arr, target, -1
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            )
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        return min_index
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    def findpeak(self, mountain_arr):
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        start = 0
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        end = mountain_arr.length() - 1
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        while start < end:
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            mid = start + int((end - start) / 2)
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            if mountain_arr.get(mid) < mountain_arr.get(mid + 1):
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                start = mid + 1
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            else:
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                end = mid
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        return start
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    def binary_search(self, start, end, mountain_arr, target, asc):
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        while start <= end:
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            mid = start + int((end - start) / 2)
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            mountain_arr_get_mid = mountain_arr.get(mid)
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            if target == mountain_arr_get_mid:
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                return mid
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            if asc == 1:
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                if target < mountain_arr_get_mid:
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                    end = mid - 1
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                elif target > mountain_arr_get_mid:
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                    start = mid + 1
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            else:
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                if target < mountain_arr_get_mid:
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                    start = mid + 1
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                elif target > mountain_arr_get_mid:
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                    end = mid - 1
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        return -1