How to add a flag to the INFO column of a vcf with pysam?

Question

[curious]

so for info content of a vcf I know I can set key value pairs like this:

vcf_in = VariantFile("chr22.vcf")

for counter, rec in enumerate(vcf_in.fetch('chr22', 10510227, 10540227)):
    rec.info["MAF"] = whatever

But I want to add something at Type=Flag, the flag IMPUTED to be more specific.

so going from and info field like this:

AF=2.33333e-05;MAF=2.33333e-05

to this:

IMPUTED;AF=2.33333e-05;MAF=2.33333e-05

Every example of setting the info attribute of the rec object seems to use key value pairs. Is setting flags possible?

[curious]

I figured it out:

vcf_in = VariantFile("chr22.vcf")
vcf_in.header.add_meta('INFO', items=[('ID',"IMPUTED"), ('Number',0), ('Type','Flag'), ('Description','Marker was imputed')])

for counter, rec in enumerate(vcf_in.fetch('chr22', 10510227, 10540227)):
    rec.info.__setitem__('IMPUTED', 1)