code: def igamma(
      a: torch.Tensor,
      /,
      *,
      x: torch.Tensor,
      out: Optional[torch.Tensor] = None,
  ) -> torch.Tensor:
      return torch.special.gammainc(a, x, out=out)
  
imports: from typing import Optional, Union, Tuple, Sequence
  import torch
  from ivy.func_wrapper import with_unsupported_dtypes, with_supported_dtypes
  from .None import backend_version
  import ivy
  from ..statistical import _infer_dtype
  from copy import deepcopy
label_desc: Use image node_id 16 for calling a global function with example usage: igamma() and returns: torch