Fix multiline signatures in docstring (#38768)

Summary:
Fix https://github.com/pytorch/pytorch/issues/38694

See https://5533621-65600975-gh.circle-artifacts.com/0/docs/torch.html

## Index Page
| Before | After |
| --- | --- |
| ![image](https://user-images.githubusercontent.com/6421097/82448124-ee1a4300-9a6e-11ea-9a48-cabf62eedd92.png)  | ![image](https://user-images.githubusercontent.com/6421097/82448175-fd00f580-9a6e-11ea-8c79-c3dd6bac0b69.png) |
| ![image](https://user-images.githubusercontent.com/6421097/82448234-0f7b2f00-9a6f-11ea-8221-19335ee60aa2.png) | ![image](https://user-images.githubusercontent.com/6421097/82448262-19049700-9a6f-11ea-9eea-ac2f71068d7f.png) |

## Detail Page
| Before | After |
| --- | --- |
| ![image](https://user-images.githubusercontent.com/6421097/82448421-4fdaad00-9a6f-11ea-9909-29692cb8ca01.png) | ![image](https://user-images.githubusercontent.com/6421097/82448440-5701bb00-9a6f-11ea-8c07-d06cb0cdfa50.png) |
| ![image](https://user-images.githubusercontent.com/6421097/82448496-68e35e00-9a6f-11ea-8db9-2d75a9328b3a.png) | ![image](https://user-images.githubusercontent.com/6421097/82448539-7567b680-9a6f-11ea-9c2e-a59eca4090c4.png) | ![image](https://user-images.githubusercontent.com/6421097/82448563-7d275b00-9a6f-11ea-97af-51f45969f473.png) |
| ![image](https://user-images.githubusercontent.com/6421097/82448329-320d4800-9a6f-11ea-8d24-3d33445cf591.png) | ![image](https://user-images.githubusercontent.com/6421097/82448353-389bbf80-9a6f-11ea-8cc8-752d3fd0dee1.png) |
Pull Request resolved: https://github.com/pytorch/pytorch/pull/38768

Differential Revision: D21691859

Pulled By: zou3519

fbshipit-source-id: 336158be450436554a1fa2105a5eedf24236c56b
diff --git a/torch/_torch_docs.py b/torch/_torch_docs.py
index 03cad7c..9ed572c 100644
--- a/torch/_torch_docs.py
+++ b/torch/_torch_docs.py
@@ -4686,9 +4686,9 @@
 """.format(**factory_like_common_args))
 
 add_docstr(torch.randint,
-           r"""
-randint(low=0, high, size, \*, generator=None, out=None, \
-        dtype=None, layout=torch.strided, device=None, requires_grad=False) -> Tensor
+           """
+randint(low=0, high, size, \\*, generator=None, out=None, \
+dtype=None, layout=torch.strided, device=None, requires_grad=False) -> Tensor
 
 Returns a tensor filled with random integers generated uniformly
 between :attr:`low` (inclusive) and :attr:`high` (exclusive).
@@ -4729,8 +4729,8 @@
 """.format(**factory_common_args))
 
 add_docstr(torch.randint_like,
-           r"""
-randint_like(input, low=0, high, dtype=None, layout=torch.strided, device=None, requires_grad=False,
+           """
+randint_like(input, low=0, high, dtype=None, layout=torch.strided, device=None, requires_grad=False, \
 memory_format=torch.preserve_format) -> Tensor
 
 Returns a tensor with the same shape as Tensor :attr:`input` filled with
@@ -6689,8 +6689,8 @@
 """.format(**factory_common_args))
 
 add_docstr(torch.full_like,
-           r"""
-full_like(input, fill_value, out=None, dtype=None, layout=torch.strided, device=None, requires_grad=False,
+           """
+full_like(input, fill_value, out=None, dtype=None, layout=torch.strided, device=None, requires_grad=False, \
 memory_format=torch.preserve_format) -> Tensor
 
 Returns a tensor with the same size as :attr:`input` filled with :attr:`fill_value`.