code: def test_missing_locus():
      input_vcf = "test-data/1kg_sample.vcf"
      mt = hl.import_vcf(input_vcf).key_rows_by("alleles").drop("locus")
      with pytest.raises(ValueError):
          functions.from_matrix_table(mt)
  
file_path: glow/python/glow/hail/tests/test_from_matrix_table.py
imports: from glow.hail import functions
  import hail
  from pyspark.sql import functions
  from pyspark.sql.types import ArrayType, StructType
  import pytest
label_desc: Use image node_id 10 for calling a global function with example usage: test_missing_locus() without return types