code: def _ready_for_het_analysis(items):
      
      paired = vcfutils.get_paired_bams([dd.get_align_bam(d) for d in items], items)
      has_het = any(dd.get_hetcaller(d) for d in items)
      if has_het and paired:
          return get_variants(paired.tumor_data) and _get_calls(paired.tumor_data, cnv_only=True)
docs: Check if a sample has input information for heterogeneity analysis.
  
      We currently require a tumor/normal sample containing both CNV and variant calls.