where to get and install crypto.dll on 64 bit Windows

Note: This is not an issue with Visual Studio, but rather with package dependencies.

When debugging, I want to be able to step into modules I have added to my Virtual Environment in Visual Studio. I get a 'library not found' error that I am not able to fix. Here are the steps:

1. In Visual Studio create a new Python Application.
2. Create a virtual environment for that application (Python 3.6 64 bit).
3. pip install twilio into your virtual environment. You get the following output.

...

   ----- Installing 'twilio' -----
Collecting twilio
  Using cached twilio-6.10.5-py2.py3-none-any.whl
Collecting pytz (from twilio)
  Using cached pytz-2018.3-py2.py3-none-any.whl
Collecting six (from twilio)
  Using cached six-1.11.0-py2.py3-none-any.whl
Collecting PyJWT>=1.4.2 (from twilio)
  Using cached PyJWT-1.6.0-py2.py3-none-any.whl
Collecting requests>=2.0.0; python_version >= "3.0" (from twilio)
  Using cached requests-2.18.4-py2.py3-none-any.whl
Collecting pysocks; python_version >= "3.0" (from twilio)
  Using cached PySocks-1.6.8.tar.gz
Collecting certifi>=2017.4.17 (from requests>=2.0.0; python_version >= "3.0"->twilio)
  Using cached certifi-2018.1.18-py2.py3-none-any.whl
Collecting chardet<3.1.0,>=3.0.2 (from requests>=2.0.0; python_version >= "3.0"->twilio)
  Using cached chardet-3.0.4-py2.py3-none-any.whl
Collecting urllib3<1.23,>=1.21.1 (from requests>=2.0.0; python_version >= "3.0"->twilio)
  Using cached urllib3-1.22-py2.py3-none-any.whl
Collecting idna<2.7,>=2.5 (from requests>=2.0.0; python_version >= "3.0"->twilio)
  Using cached idna-2.6-py2.py3-none-any.whl
Installing collected packages: pytz, six, PyJWT, certifi, chardet, urllib3, idna, requests, pysocks, twilio
  Running setup.py install for pysocks: started
    Running setup.py install for pysocks: finished with status 'done'
Successfully installed PyJWT-1.6.0 certifi-2018.1.18 chardet-3.0.4 idna-2.6 pysocks-1.6.8 pytz-2018.3 requests-2.18.4 six-1.11.0 twilio-6.10.5 urllib3-1.22
----- Successfully installed 'twilio' -----

4. Add the following line to the top of your .py file:

   from twilio.rest import Client

5. In Visual Studio go to tools > options > python > debugging. Make sure 'Enable debugging of Python standard library' is checked

6. Run the application. You get the following error:

ModuleNotFoundError: No module named 'OpenSSL'

7. pip install pyopenssl You get the following output:

...

----- Installing 'pyopenssl' -----
Collecting pyopenssl
  Using cached pyOpenSSL-17.5.0-py2.py3-none-any.whl
Requirement already satisfied: six>=1.5.2 in c:\users\x\source\repos\pythonapplication9\pythonapplication9\env\lib\site-packages (from pyopenssl)
Collecting cryptography>=2.1.4 (from pyopenssl)
  Using cached cryptography-2.1.4-cp36-cp36m-win_amd64.whl
Requirement already satisfied: idna>=2.1 in c:\users\x\source\repos\pythonapplication9\pythonapplication9\env\lib\site-packages (from cryptography>=2.1.4->pyopenssl)
Collecting cffi>=1.7; platform_python_implementation != "PyPy" (from cryptography>=2.1.4->pyopenssl)
  Using cached cffi-1.11.5-cp36-cp36m-win_amd64.whl
Collecting asn1crypto>=0.21.0 (from cryptography>=2.1.4->pyopenssl)
  Using cached asn1crypto-0.24.0-py2.py3-none-any.whl
Collecting pycparser (from cffi>=1.7; platform_python_implementation != "PyPy"->cryptography>=2.1.4->pyopenssl)
  Using cached pycparser-2.18.tar.gz
Installing collected packages: pycparser, cffi, asn1crypto, cryptography, pyopenssl
  Running setup.py install for pycparser: started
    Running setup.py install for pycparser: finished with status 'done'
Successfully installed asn1crypto-0.24.0 cffi-1.11.5 cryptography-2.1.4 pycparser-2.18 pyopenssl-17.5.0
----- Successfully installed 'pyopenssl' -----

8. Run the application. You get the following error:

   asn1crypto._ffi.LibraryNotFoundError: The library libcrypto could not be found

The error is thrown in the file named _big_num_ctypes.py in asn1crypto. The code line where this is thrown is:

libcrypto_path = find_library(b'crypto' if sys.version_info < (3,) else 'crypto')
if not libcrypto_path:
    raise LibraryNotFoundError('The library libcrypto could not be found')

Update: I was asked to provide the full backtrace. I modified the code in this way to print it:

import unittest
import traceback

class Test_test1(unittest.TestCase):
    def test_A(self):
        try:
            from twilio.rest import Client
        except Exception as e:
            print('foo')
            foo = traceback.extract_stack()
            traceback.print_exc(e)

if __name__ == '__main__':
    unittest.main()

As before the import line throws the exception but the exception is not caught and the lines in 'except' clause are never executed from twilio.rest import Client

update 2: I somehow had gotten this to work following @Prateek and @user8212173. But now it is not working again. As both suggested, the problem is that crypto.dll is not there. So I went thru the steps below to add it with no success:

1. I installed Win64 OpenSSL v1.1.0j from https://slproweb.com/products/Win32OpenSSL.html (pointed to from https://wiki.openssl.org/index.php/Binaries). It does not contain crypto.dll.
2. I then installed crypto.dll from http://www.dlldownloader.com/crypto-dll/ (as @user8212173 suggested) (there is only a 32 bit version) and followed the instructions. I then got a new error message "ImportError: DLL load failed: %1 is not a valid Win32 application" which means that the crypto.dll I installed has a version conflict (I am running 64bit python on a 64bit computer). I remember installing it from https://www.lfd.uci.edu/~gohlke/pythonlibs/ I can't find it there. So where do I get a working 64bit version of crypto.cll?

from where to get and install crypto.dll on 64 bit Windows