class_docstr: An object that represents an individual's call at a genomic locus.
  
  Parameters
  ----------
  alleles : :obj:`list` of :obj:`int`
      List of alleles that compose the call.
  phased : :obj:`bool`
      If ``True``, the alleles are phased and the order is specified by
      `alleles`.
  
  Note
  ----
  This object refers to the Python value returned by taking or collecting
  Hail expressions, e.g. ``mt.GT.take(5`)``. This is rare; it is much
  more common to manipulate the :class:`.CallExpression` object, which is
  constructed using the following functions:
  
   - :func:`.call`
   - :func:`.unphased_diploid_gt_index_call`
   - :func:`.parse_call`
docstr: Returns the count of non-reference alleles.
  
  :rtype: int
docstr_tok: ["Returns","the","count","of","non-reference","alleles",".",":","rtype",":","int"]
code: def n_alt_alleles(self):
      """Returns the count of non-reference alleles.
  
      :rtype: int
      """
      n = 0
      for a in self._alleles:
          if a > 0:
              n += 1
      return n
  
imports: from collections.abc import Sequence
  from hail.typecheck import typecheck_method
  from hail.utils import FatalError
label_desc: Use image node_id 18 for calling the Call obj's underlying member method code with example usage: obj.n_alt_alleles() and returns: n