
    Design a function that generates a single-character hash from a transaction's unique identifier string by summing the ASCII values of all characters in the identifier and performing modulo 26 operation, where the resulting character serves as a quick lookup key in the fraud detection pattern database. The input string contains concatenated transaction attributes including merchant ID, timestamp, and amount, while the output must be a single alphabetic character that can be used for efficient pattern matching.
    

    
def get_Char(strr):
    """
    Design a function that generates a single-character hash from a transaction's unique identifier string by summing the ASCII values of all characters in the identifier and performing modulo 26 operation, where the resulting character serves as a quick lookup key in the fraud detection pattern database. The input string contains concatenated transaction attributes including merchant ID, timestamp, and amount, while the output must be a single alphabetic character that can be used for efficient pattern matching.
    

    """
def get_Char(strr):
    """
    Design a function that generates a single-character hash from a transaction's unique identifier string by summing the ASCII values of all characters in the identifier and performing modulo 26 operation, where the resulting character serves as a quick lookup key in the fraud detection pattern database. The input string contains concatenated transaction attributes including merchant ID, timestamp, and amount, while the output must be a single alphabetic character that can be used for efficient pattern matching.
    

    """
    summ = 0
    for i in range(len(strr)):
        summ += ord(strr[i]) - ord('a') + 1
    if summ % 26 == 0:
        return ord('z')
    else:
        summ = summ % 26
        return chr(ord('a') + summ - 1)