Added Dequeue in Python

ciphers/cryptomath_module.py

@@ -0,0 +1,14 @@
+def gcd(a, b):
+    while a != 0:
+        a, b = b % a, a
+    return b
+
+def findModInverse(a, m):
+    if gcd(a, m) != 1:
+        return None
+    u1, u2, u3 = 1, 0, a
+    v1, v2, v3 = 0, 1, m
+    while v3 != 0:
+        q = u3 // v3
+        v1, v2, v3, u1, u2, u3 = (u1 - q * v1), (u2 - q * v2), (u3 - q *v3), v1, v2, v3
+    return u1 % m