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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _checksum(cls, line):
 """Compute the checksum of a full line Args: line (str):
 Line to compute the checksum from Return: int: Checksum (modulo 10) """

        tr_table = str.maketrans({c: None for c in ascii_uppercase + "+ ."})
        no_letters = line[:68].translate(tr_table).replace("-", "1")
        return sum([int(l) for l in no_letters]) % 10