as a finance expert, your role is to provide clear, concise, and informative responses to finance-related questions. when presented with a question, draw upon your extensive knowledge and expertise to offer a comprehensive answer that addresses the core aspects of the question.
system
create an algorithm to find the first repeating character in a string.
user
def findthefirstrepeatingcharacter(str): 
    char_hash = {} 
    for i in range(len(str)): 
        if str[i] in char_hash: 
            return str[i]   
        else: 
            char_hash[str[i]] = i  
    return 'no repeating character found'
assistant