QST: build offline?
- [x ] I have searched the [[pandas] tag](https://stackoverflow.com/questions/tagged/pandas) on StackOverflow for similar questions.

- [ n/a] I have asked my usage related question on [StackOverflow](https://stackoverflow.com).

---

#### Question about pandas

**Note**: If you'd still like to submit a question, please read [this guide](
https://matthewrocklin.com/blog/work/2018/02/28/minimal-bug-reports) detailing how to provide the necessary information for us to reproduce your question.

```python
# Your code here, if applicable

[40/40] Cythonizing pandas/io/sas/sas.pyx
Traceback (most recent call last):
  File "/usr/lib/python3.7/urllib/request.py", line 1317, in do_open
    encode_chunked=req.has_header('Transfer-encoding'))
  File "/usr/lib/python3.7/http/client.py", line 1229, in request
    self._send_request(method, url, body, headers, encode_chunked)
  File "/usr/lib/python3.7/http/client.py", line 1275, in _send_request
    self.endheaders(body, encode_chunked=encode_chunked)
  File "/usr/lib/python3.7/http/client.py", line 1224, in endheaders
    self._send_output(message_body, encode_chunked=encode_chunked)
  File "/usr/lib/python3.7/http/client.py", line 1016, in _send_output
    self.send(msg)
  File "/usr/lib/python3.7/http/client.py", line 956, in send
    self.connect()
  File "/usr/lib/python3.7/site-packages/setuptools/ssl_support.py", line 174, in connect
    (self.host, self.port), getattr(self, 'source_address', None)
  File "/usr/lib/python3.7/socket.py", line 707, in create_connection
    for res in getaddrinfo(host, port, 0, SOCK_STREAM):
  File "/usr/lib/python3.7/socket.py", line 748, in getaddrinfo
    for res in _socket.getaddrinfo(host, port, family, type, proto, flags):
socket.gaierror: [Errno -2] Name or service not known

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/lib/python3.7/site-packages/setuptools/package_index.py", line 764, in open_url
    return open_with_auth(url, self.opener)
  File "/usr/lib/python3.7/site-packages/setuptools/package_index.py", line 951, in _socket_timeout
    return func(*args, **kwargs)
  File "/usr/lib/python3.7/site-packages/setuptools/package_index.py", line 1070, in open_with_auth
    fp = opener(request)
  File "/usr/lib/python3.7/urllib/request.py", line 525, in open
    response = self._open(req, data)
  File "/usr/lib/python3.7/urllib/request.py", line 543, in _open
    '_open', req)
  File "/usr/lib/python3.7/urllib/request.py", line 503, in _call_chain
    result = func(*args)
  File "/usr/lib/python3.7/site-packages/setuptools/ssl_support.py", line 161, in https_open
    lambda host, **kw: VerifyingHTTPSConn(host, self.ca_bundle, **kw), req
  File "/usr/lib/python3.7/urllib/request.py", line 1319, in do_open
    raise URLError(err)
urllib.error.URLError: <urlopen error [Errno -2] Name or service not known>

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "setup.py", line 761, in <module>
    setup_package()
  File "setup.py", line 754, in setup_package
    **setuptools_kwargs,
  File "/usr/lib/python3.7/site-packages/setuptools/__init__.py", line 128, in setup
    _install_setup_requires(attrs)
  File "/usr/lib/python3.7/site-packages/setuptools/__init__.py", line 123, in _install_setup_requires
    dist.fetch_build_eggs(dist.setup_requires)
  File "/usr/lib/python3.7/site-packages/setuptools/dist.py", line 513, in fetch_build_eggs
    replace_conflicting=True,
  File "/usr/lib/python3.7/site-packages/pkg_resources/__init__.py", line 774, in resolve
    replace_conflicting=replace_conflicting
  File "/usr/lib/python3.7/site-packages/pkg_resources/__init__.py", line 1057, in best_match
    return self.obtain(req, installer)
  File "/usr/lib/python3.7/site-packages/pkg_resources/__init__.py", line 1069, in obtain
    return installer(requirement)
  File "/usr/lib/python3.7/site-packages/setuptools/dist.py", line 580, in fetch_build_egg
    return cmd.easy_install(req)
  File "/usr/lib/python3.7/site-packages/setuptools/command/easy_install.py", line 661, in easy_install
    not self.always_copy, self.local_index
  File "/usr/lib/python3.7/site-packages/setuptools/package_index.py", line 653, in fetch_distribution
    dist = find(requirement)
  File "/usr/lib/python3.7/site-packages/setuptools/package_index.py", line 633, in find
    loc = self.download(dist.location, tmpdir)
  File "/usr/lib/python3.7/site-packages/setuptools/package_index.py", line 577, in download
    found = self._download_url(scheme.group(1), spec, tmpdir)
  File "/usr/lib/python3.7/site-packages/setuptools/package_index.py", line 822, in _download_url
    return self._attempt_download(url, filename)
  File "/usr/lib/python3.7/site-packages/setuptools/package_index.py", line 828, in _attempt_download
    headers = self._download_to(url, filename)
  File "/usr/lib/python3.7/site-packages/setuptools/package_index.py", line 727, in _download_to
    fp = self.open_url(url)
  File "/usr/lib/python3.7/site-packages/setuptools/package_index.py", line 778, in open_url
    % (url, v.reason))
distutils.errors.DistutilsError: Download error for https://files.pythonhosted.org/packages/a9/03/5b216f6a55ffc6bdac3ad3a896c58d4f17d99e18ff82fc68363df7d6a7b3/numpy-1.20.2-cp37-cp37m-manylinux1_x86_64.whl#sha256=9cab23439eb1ebfed1aaec9cd42b7dc50fc96d5cd3147da348d9161f0501ada5: [Errno -2] Name or service not known

```
I am building on a machine that CANNOT access the internet. I already have numpy etc., yet setup.py will not
allow me to build pandas.

Q: how to build offline?
