database_stein_watkins Python 3 issues

[vbraun]

There seem to be various places with bytes / string confusion when building on Python 3, e.g.:

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File "src/sage/databases/stein_watkins.py", line 50, in sage.databases.stein_watkins
Failed example:
    next(d)                                       # optional - database_stein_watkins
Exception raised:
    Traceback (most recent call last):
      File "/var/lib/buildbot/slave/sage_git/build/local/lib/python3.7/site-packages/sage/doctest/forker.py", line 681, in _run
        self.compile_and_execute(example, compiler, test.globs)
      File "/var/lib/buildbot/slave/sage_git/build/local/lib/python3.7/site-packages/sage/doctest/forker.py", line 1123, in compile_and_execute
        exec(compiled, globs)
      File "<doctest sage.databases.stein_watkins[4]>", line 1, in <module>
        next(d)                                       # optional - database_stein_watkins
      File "/var/lib/buildbot/slave/sage_git/build/local/lib/python3.7/site-packages/sage/databases/stein_watkins.py", line 242, in __next__
        return next(self._iter)
      File "/var/lib/buildbot/slave/sage_git/build/local/lib/python3.7/site-packages/sage/databases/stein_watkins.py", line 228, in __iter__
        N = int(x[0])
    ValueError: invalid literal for int() with base 10: b'[0,-1,1,0,0]'
**********************************************************************

CC: @williamstein @sagetrac-kimball

Component: packages: optional

Keywords: databases, stein-watkins

Author: Alex J. Best

Branch/Commit: ef49c0a

Reviewer: Markus Wageringel

Issue created by migration from https://trac.sagemath.org/ticket/28816

[embray]

comment:1

Ticket retargeted after milestone closed

[alexjbest]

Branch: u/alexjbest/stein-watkins

[alexjbest]

comment:4

I tried to fix this, as I understand it 9.2 will be python2 incompatible so I didn't worry about backwards compatibility.

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New commits:

ef49c0a

fix file encoding for Stein-Watkins database in python3

[alexjbest]

Commit: ef49c0a

[alexjbest]

Author: Alex J. Best

[alexjbest]

Changed keywords from none to databases, stein-watkins

[mwageringel]

Reviewer: Markus Wageringel

[mwageringel]

comment:6

Ok, this works for me.

[vbraun]

Changed branch from u/alexjbest/stein-watkins to ef49c0a