initial commit

longrandom.py

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+import math, os
+from functools import reduce
+
+log256 = math.log(256)
+
+class LongRandom:
+	def getint(self, bytes):
+		value = list(os.urandom(bytes))
+		return reduce(lambda x,y: (x<<8)|y, value)
+	def get(self, modulus):
+		# Find the largest power-of-2 that modulus fits into
+		bytes = int(math.ceil(math.log(modulus) / log256))
+		maxval = 256 ** bytes
+		# maxmod is the largest multiple of modulus not greater than maxval
+		maxmult = maxval - maxval % modulus
+		while True:
+			value = self.getint(bytes)
+			# Stop generating when the value would not cause bias
+			if value <= maxmult:
+				break
+		return value % modulus