Determines if a string has all unique characters.

IsUnique.py

def unique_str(str):
    unique = ""
    for char in str:
        if char not in unique:
            unique += char
        else:
            continue
    
    if unique == str:
        print(True)
    else:
        print(False)


# unique_str("abcdef")
# unique_str("abcdddef")
# unique_str("0")