code: def has_deletion(variant):
      """Does variant have a deletion?
  
      Args:
        variant: nucleus.genomics.v1.Variant.
  
      Returns:
        True if the alleles in variant indicate an deletion event
        occurs at this site.
      """
      ref = variant.reference_bases
      return is_indel(variant) and any(
          is_deletion(ref, alt) for alt in variant.alternate_bases
      )
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import collections
  import enum
  import itertools
  import six
  from third_party.nucleus.protos import variants_pb2
  from third_party.nucleus.util import ranges
  from third_party.nucleus.util import variantcall_utils
  from third_party.nucleus.util import vcf_constants
label_desc: Use image node_id 22 for calling a global function with example usage: has_deletion(variant) and returns: unknown