Operating rules

• Use Python requests for all network calls.
• Accept exactly one of rsid, grch37, grch38, or variant, and resolve to a GRCh38 chrom-pos-ref-alt query.
• Convert to GTEx variantId format: chr{chrom}_{pos}_{ref}_{alt}_b38.
• Always return one JSON object (no markdown) as final output.

Input

Accept JSON on stdin as either:

• A string: "10-112998590-C-T" (treated as GRCh38)
• An object:

{
  "grch38": "10-112998590-C-T",
  "max_results": 200
}