ParmEdConverter: fix NameError when catching NoDataError

[cbouy]

Converting to parmed when the AtomGroup doesn't have a resname leads to a NameError: the current code tries to catch the NoDataError but because NoDataError is not imported from exceptions.py it triggers a NameError: name 'NoDataError' is not defined

Changes made in this Pull Request:

• import NoDataError from exceptions

Is the changelog update needed here ?

PR Checklist

• Tests?
• Docs?
• CHANGELOG updated?
• Issue raised/referenced?

[codecov]

Codecov Report

Merging #2953 into develop will increase coverage by 0.03%.
The diff coverage is 100.00%.

@@             Coverage Diff             @@
##           develop    #2953      +/-   ##
===========================================
+ Coverage    93.05%   93.09%   +0.03%     
===========================================
  Files          186      186              
  Lines        24613    24663      +50     
  Branches      3187     3197      +10     
===========================================
+ Hits         22904    22959      +55     
+ Misses        1661     1656       -5     
  Partials        48       48              

Impacted Files	Coverage Δ
package/MDAnalysis/coordinates/ParmEd.py	90.96% <100.00%> (+4.17%)	⬆️
package/MDAnalysis/transformations/translate.py	95.23% <0.00%> (-4.77%)	⬇️
package/MDAnalysis/topology/ParmEdParser.py	98.44% <0.00%> (-0.05%)	⬇️
util.py	89.47% <0.00%> (ø)
package/MDAnalysis/lib/util.py	90.05% <0.00%> (ø)
package/MDAnalysis/analysis/msd.py	100.00% <0.00%> (ø)
package/MDAnalysis/analysis/pca.py	98.65% <0.00%> (ø)
package/MDAnalysis/analysis/rdf.py	100.00% <0.00%> (ø)
package/MDAnalysis/analysis/dihedrals.py	100.00% <0.00%> (ø)
package/MDAnalysis/analysis/hole2/hole.py	73.19% <0.00%> (ø)
... and 9 more

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[lilyminium]

Oops, thanks for finding this. Could you please add a test as well so the tests will catch it in the future as well?

[orbeckst]

You don't need to update the CHANGELOG as this just fixes something that hadn't been released yet. (We don't absolutely strictly adhere to what I just said because our release cycles are so stretched out that we need to track bugs in develop and often fix issues that never show up in a released version. But in the case here a CHANGELOG entry seems overkill.)

[orbeckst]

Can you please add a test?

Not for testing that your fix worked but rather because it indicates that we didn't test a possible (and perhaps not uncommon) failure mode earlier.

[pep8speaks]

Hello @cbouy! Thanks for updating this PR. We checked the lines you've touched for PEP 8 issues, and found:

There are currently no PEP 8 issues detected in this Pull Request. Cheers! 🍻

Comment last updated at 2020-10-29 16:15:54 UTC

[cbouy]

Sorry for the delay and the messed up commits, should be fixed now

[orbeckst]

Thank you!