License Key Formatting

License Key Formatting.py

class Solution:
    def licenseKeyFormatting(self, S, K):
        """
        :type S: str
        :type K: int
        :rtype: str
        """
        S =''.join(S.split('-'))
        S = str.upper(S)
        temp = ''
        len_S = len(S)
        
        first = len(S) % K
        count = 0
        
        if len_S < K:
            return S
        
        if first != 0:
            temp = S[:first] + '-'
            
        for s in S[first:]:
            count += 1
            temp += s 
            if count % K == 0 and count < len_S - first:
                temp += '-'
        
        return temp