Number of Ways to Stay in the Same Place After Some Steps LeetCode solution in Python

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class Solution:
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    def numWays(self, steps: int, arrLen: int) -> int:
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        # obtain maximum index we can reach
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        maxLen = min(steps + 1, arrLen)
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        dp = [0] * maxLen
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        dp[0] = 1
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        for step in range(1, steps + 1):
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            dp2 = [0] * maxLen
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            for pos in range(maxLen):
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                # dp[step][pos] = dp[step-1][pos] + dp[step-1][pos-1] + dp[step-1][pos+1]
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                temp1 = 0 if pos == 0 else dp[pos - 1]
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                temp2 = 0 if pos == maxLen - 1 else dp[pos + 1]
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                dp2[pos] = (dp[pos] + temp1 + temp2) % (10**9 + 7)
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            dp = dp2
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        return dp[0]