Bug due to python3 upgrade at ECMWF ecgate env

[anphi]

After the ECMWF announced a couple of software upgrades and change to new default versions (​https://confluence.ecmwf.int/display/UDOC/2021/03/10/Change+of+default+versions+of+ECMWF+and+third-party+software+packages+-+May+2021), the software runs into an error when retrieving ERA5 data:

$HOME/flex_extract_v7.1.2_ctbto/Source/Python/Mods/checks.py:94: SyntaxWarning: 'str' object is not callable; perhaps you missed a comma?
  raise ValueError('GRID parameter contains two '
$HOME/flex_extract_v7.1.2_ctbto/Source/Python/Mods/checks.py:819: SyntaxWarning: "is not" with a literal. Did you mean "!="?
  parlist = [p for p in parlist if p is not '']
Retrieving ECMWF data and printing MARS request!
start date 20140617 
end date 20140621 
Traceback (most recent call last):
  File "$HOME/flex_extract_v7.1.2_ctbto/Source/Python/submit.py", line 268, in <module>
    main()
  File "$HOME/flex_extract_v7.1.2_ctbto/Source/Python/submit.py", line 107, in main
    get_mars_data(c)
  File "$HOME/flex_extract_v7.1.2_ctbto/Source/Python/Mods/get_mars_data.py", line 150, in get_mars_data
    server = mk_server(c)
  File "$HOME/flex_extract_v7.1.2_ctbto/Source/Python/Mods/get_mars_data.py", line 211, in mk_server
    server = cdsapi.Client()
  File "/usr/local/apps/cdsapi/0.5.1/lib/python3.8/site-packages/cdsapi/api.py", line 301, in __init__
    raise Exception("Missing/incomplete configuration file: %s" % (dotrc))
Exception: Missing/incomplete configuration file: $HOME/.cdsapirc