The following constants are also available as vcfpy.CONSTANT.
vcfpy.record.HOM_REF
vcfpy.record.HOM_ALT
vcfpy.record.FIVE_PRIME
vcfpy.record.THREE_PRIME
vcfpy.record.FORWARD
vcfpy.record.REVERSE
vcfpy.Record
vcfpy.Call
vcfpy.AltRecord
vcfpy.Substitution
vcfpy.SV
vcfpy.BreakEnd
vcfpy.SingleBreakEnd
vcfpy.SymbolicAllele