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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 include_block(self, x):
 """Check for inclusion of block based on distance from previous. """

        last_pos = self._chr_last_blocks.get(x.chrom, 0)
        # Region excludes an entire chromosome, typically decoy/haplotypes
        if last_pos <= self._end_buffer and x.stop >= self._ref_sizes.get(x.chrom, 0) - self._end_buffer:
            return True
        # Do not split on smaller decoy and haplotype chromosomes
        elif self._ref_sizes.get(x.chrom, 0) <= self._target_size:
            return False
        elif (x.start - last_pos) > self._target_size:
            self._chr_last_blocks[x.chrom] = x.stop
            return True
        else:
            return False