while executing get_SNP_candidates.py and get_tensors gave this error

[siddhantrathore]

Traceback (most recent call last): File "get_SNP_candidates.py", line 172, in make_variant_candidates(args) File "get_SNP_candidates.py", line 103, in make_variant_candidates pileup[pos][b] += 1 KeyError: 'N' samtools view: writing to standard output failed: Broken pipe samtools view: error closing standard output: -1