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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 _getBlock(self, block_spec):
 """ Returns block info from given block start code point or block name. """

        if block_spec is None:
            return
        if all(c in string.hexdigits for c in block_spec):
            block_spec = block_spec.upper()
            ix = 0
        else:
            ix = 2
        for block in all_blocks:
            if block[ix] == block_spec:
                return block
        raise ValueError('No such block')