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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 _check_validity(cls, text):
 """Check the validity of a TLE Args: text (tuple of str) Raise: ValueError """


        if not text[0].lstrip().startswith('1 ') or not text[1].lstrip().startswith('2 '):
            raise ValueError("Line number check failed")

        for line in text:
            line = line.strip()
            if str(cls._checksum(line)) != line[-1]:
                raise ValueError("Checksum validation failed")