Reverse Iteration Cipher in Python 3 (part 3)

import random;


# Reverse iterate
def revpow2(z, c, b):
     if b == 1:
            return -((z-c)**(0.5));
     else:
            return (z-c)**(0.5);


# Forward iterate
def fowpow2(z, c):
     return z * z + c;


# Encrypt bits
def encrypt_bits(z, c, pt):
    for b in pt:
        z=revpow2(z,c,int(b));
        print(z);
    return z;


# Decrypts bits
def decrypt_bits(z, c, n):
    s = ""
    for b in range(n):
        print(z);
        s += "0" if z.real > 0 else "1";
        z = fowpow2(z,c);
    s = s[::-1]; # reverse the bits
    return s;


# Generate random z
def randz(nmin, nmax):
    d = nmax - nmin;
    x = nmin + random.random() * d;
    y = nmin + random.random() * d;
    return complex(x, y);




# The secret key (c), and origin point (z)
c = (-.75+.09j);
z = randz(-9999999999, 9999999999);
pt0 = "01000001010000010100000101000001";
n = len(pt0);


print("c:" + str(c));
print("z:" + str(z));
print("n:" + str(n));
print("");


print("Encrypt: " + pt0);
print("______________________________________");
ct = encrypt_bits(z, c, pt0);
print("______________________________________");
print("");


print("Decrypt");
print("______________________________________");
pt1 = decrypt_bits(ct, c, n);
print("______________________________________");
print("");

print("Decrypted: " + pt1);

if pt0 != pt1: print("DATA CORRUPTED!!");