pip install fts3-rest results in broken deployment

[paulmillar]

On my Debian GNU/Linux 10 (buster) machine, I have fts3-rest client installed via pip.

paul@sprocket:~$ pip2 install fts3-rest
/home/paul/.local/lib/python2.7/site-packages/cryptography/__init__.py:39: CryptographyDeprecationWarning: Python 2 is no longer supported by the Python core team. Support for it is now deprecated in cryptography, and will be removed in a future release.
  CryptographyDeprecationWarning,
Requirement already satisfied: fts3-rest in ./.local/lib/python2.7/site-packages (3.10.0)
Requirement already satisfied: pycurl==7.19.0 in ./.local/lib/python2.7/site-packages (from fts3-rest) (7.19.0)
Requirement already satisfied: requests in ./.local/lib/python2.7/site-packages (from fts3-rest) (2.23.0)
Requirement already satisfied: M2Crypto>=0.16 in ./.local/lib/python2.7/site-packages (from fts3-rest) (0.35.2)
Requirement already satisfied: liboidcagent>=0.2.2 in ./.local/lib/python2.7/site-packages (from fts3-rest) (0.2.2)
Requirement already satisfied: idna<3,>=2.5 in ./.local/lib/python2.7/site-packages (from requests->fts3-rest) (2.10)
Requirement already satisfied: urllib3!=1.25.0,!=1.25.1,<1.26,>=1.21.1 in ./.local/lib/python2.7/site-packages (from requests->fts3-rest) (1.25.9)
Requirement already satisfied: certifi>=2017.4.17 in ./.local/lib/python2.7/site-packages (from requests->fts3-rest) (2020.6.20)
Requirement already satisfied: chardet<4,>=3.0.2 in ./.local/lib/python2.7/site-packages (from requests->fts3-rest) (3.0.4)
Requirement already satisfied: typing in ./.local/lib/python2.7/site-packages (from M2Crypto>=0.16->fts3-rest) (3.7.4.1)
paul@sprocket:~$ 

I have a valid credential:

paul@sprocket:~$ voms-proxy-info --all
subject   : /C=DE/O=GermanGrid/OU=DESY/CN=Robot - grid client - Paul Millar (client software tester)/CN=1331207800
issuer    : /C=DE/O=GermanGrid/OU=DESY/CN=Robot - grid client - Paul Millar (client software tester)
identity  : /C=DE/O=GermanGrid/OU=DESY/CN=Robot - grid client - Paul Millar (client software tester)
type      : RFC3820 compliant impersonation proxy
strength  : 2048
path      : /tmp/x509up_u1000
timeleft  : 09:10:50
key usage : Digital Signature, Key Encipherment, Data Encipherment
=== VO dteam extension information ===
VO        : dteam
subject   : /C=DE/O=GermanGrid/OU=DESY/CN=Robot - grid client - Paul Millar (client software tester)
issuer    : /C=GR/O=HellasGrid/OU=hellasgrid.gr/CN=voms2.hellasgrid.gr
attribute : /dteam/Role=NULL/Capability=NULL
timeleft  : 09:10:50
uri       : voms2.hellasgrid.gr:15004

paul@sprocket:~$ 

... however, it doesn't seem to work:

paul@sprocket:~$ fts-rest-whoami 
Traceback (most recent call last):
  File "/home/paul/.local/bin/fts-rest-whoami", line 2, in <module>
    from fts3.cli import WhoAmI
  File "/home/paul/.local/lib/python2.7/site-packages/fts3/cli/__init__.py", line 18, in <module>
    from banning import Banning
  File "/home/paul/.local/lib/python2.7/site-packages/fts3/cli/banning.py", line 18, in <module>
    from base import Base
  File "/home/paul/.local/lib/python2.7/site-packages/fts3/cli/base.py", line 26, in <module>
    from fts3.rest.client import Context
  File "/home/paul/.local/lib/python2.7/site-packages/fts3/rest/client/__init__.py", line 19, in <module>
    from context import Context
  File "/home/paul/.local/lib/python2.7/site-packages/fts3/rest/client/context.py", line 35, in <module>
    from pycurlRequest import PycurlRequest
  File "/home/paul/.local/lib/python2.7/site-packages/fts3/rest/client/pycurlRequest.py", line 22, in <module>
    import pycurl
ImportError: /usr/lib/x86_64-linux-gnu/libcurl.so.4: version `CURL_OPENSSL_3' not found (required by /home/paul/.local/lib/python2.7/site-packages/pycurl.so)
paul@sprocket:~$ 

If it helps, here is my FTS-client configuration:

paul@sprocket:~$ cat ~/.fts3client.cfg 
[Main]
endpoint=https://fts3-xdc.cern.ch:8446
oidc-agent-account = XDC
oidc-agent-audience = https://wlcg.cern.ch/jwt/v1/any
paul@sprocket:~$