'str' object is not callable

[ZYSIA]

this is my script below :
when i first run, everything is normal and prompt user "Do you want a new reading :"
but when i key in yes and the error 'str' object is not callable came out on this line "hex_number = str(hex(randomnumber))"
any idea how to solve this issue? i've check and confirm i dont have another str define else where ..

def main():    

    import random
    global hex
    

    randomnumber = random.randint(0,99)

    hex_number = str(hex(randomnumber))
    hex_numberd0 = '0x' + hex_number[2:]
    print('A random D0:', hex_number)

    randomnumber = random.randint(0,99)
    hex_number = str(hex(randomnumber))
    hex_numberd1 = '0x' + hex_number[2:]
    print('A random D1:', hex_number)

    randomnumber = random.randint(0,99)
    hex_number = str(hex(randomnumber))
    hex_numberd2 = '0x' + hex_number[2:]
    print('A random D2:', hex_number)

    D0 = hex_numberd0
    D1 = hex_numberd1
    D2 = hex_numberd2

    #hex coversion
    hex= D0
    dec0 = int(hex,16)
    print('Value in hexadecimal D0 :', hex)
    print('Value in decimal D0 :', dec0)

    hex= D1
    dec1 = int(hex,16)
    print('Value in hexadecimal D1 :', hex)
    print('Value in decimal D1 :', dec0)

    hex= D2
    dec2 = int(hex,16)
    print('Value in hexadecimal D2 :', hex)
    print('Value in decimal D2 :', dec0)

    #coversion ends
    
    #inclination calculation

    if(dec2 >> 7 == 1):
           signbit = -1
    else:
            signbit = 1

    Data0 = (dec0 >> 6)
    Data1 = (dec1 <<2)
    Data2 = ((dec2&127)<<10)

    print("D0 =", Data0)
    print("D1 =", Data1)
    print("D2 =", Data2)

    DataI = signbit*(Data0 + Data1 + Data2)/1000
    print("inclination = ", DataI)

    restart = input("Do you want a new reading :   ").lower()
    if restart == "yes":
        main()

    else:
        exit()
main()

Yoriz write Jul-28-2021, 09:39 AM:
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