This kata requires you to convert minutes (`int`) to hours and minutes in the format `hh:mm` (`string`).
If the input is `0` or negative value, then you should return `"00:00"`
**Hint:** use the modulo operation to solve this challenge. The modulo operation simply returns the remainder after a division. For example the remainder of 5 / 2 is 1, so 5 modulo 2 is 1.
## Example
If the input is `78`, then you should return `"01:18"`, because 78 minutes converts to 1 hour and 18 minutes.
Good luck! :D
def time_convert(num):
    a=num//60
    b=num%60
    if num<=0:
        return '00:00'
    elif 0<num<10:
        return '00:0'+str(num)
    elif 10<=num<60:
        return '00:'+str(num)
    else:
        if a<10 and b<10:
            return "0"+str(a)+':'+"0"+str(b)
        elif a>=10 and b<10:
            return str(a)+':'+"0"+str(b)
        elif a<10 and b>=10:
            return "0"+str(a)+':'+str(b)
        elif a>=10 and b>=10:
            return str(a)+':'+str(b)
def time_convert(num):
    a=num//60
    b=num%60
    if num<=0:
        return '00:00'
    elif 0<num<10:
        return '00:0'+str(num)
    elif 10<=num<60:
        return '00:'+str(num)
    else:
        if a<10 and b<10:
            return "0"+str(a)+':'+"0"+str(b)
        elif a>=10 and b<10:
            return str(a)+':'+"0"+str(b)
        elif a<10 and b>=10:
            return "0"+str(a)+':'+str(b)
        elif a>=10 and b>=10:
            return str(a)+':'+str(b)