gh-37273: large pep8 cleanup in interfaces
    
just fixing many small code details in `interfaces` folder

### 📝 Checklist

- [x] The title is concise, informative, and self-explanatory.
- [x] The description explains in detail what this PR is about.
    
URL: #37273
Reported by: Frédéric Chapoton
Reviewer(s): Frédéric Chapoton, Kwankyu Lee

Author: Release Manager

src/sage/interfaces/abc.py

@@ -2,6 +2,7 @@
 Abstract base classes for interface elements
 """
 
+
 class AxiomElement:
     r"""
     Abstract base class for :class:`~sage.interfaces.axiom.AxiomElement`.

src/sage/interfaces/all.py

@@ -4,7 +4,7 @@
 from .gap import gap, gap_reset_workspace, Gap
 from .gp import gp, gp_version, Gp
 # import problems
-#from maxima_lib import maxima_lib
+# from maxima_lib import maxima_lib
 from .maxima import maxima, Maxima
 from .singular import singular, singular_version, Singular
 

src/sage/interfaces/chomp.py

@@ -19,6 +19,8 @@
 from sage.misc.superseded import deprecation
 
 _have_chomp = {}
+
+
 def have_chomp(program='homsimpl'):
     """
     Return True if this computer has ``program`` installed.
@@ -394,7 +396,7 @@ def __call__(self, program, complex, subcomplex=None, **kwds):
             for dim in d:
                 if complex._degree_of_differential == -1:  # chain complex
                     new_dim = bottom + dim
-                else: # cochain complex
+                else:  # cochain complex
                     new_dim = top - dim
                 if isinstance(d[dim], tuple):
                     # generators included.
@@ -512,6 +514,7 @@ def homsimpl(complex=None, subcomplex=None, **kwds):
     else:
         raise TypeError("Complex and/or subcomplex are not simplicial complexes.")
 
+
 def homcubes(complex=None, subcomplex=None, **kwds):
     r"""
     Compute the homology of a cubical complex using the CHomP program
@@ -743,6 +746,7 @@ def process_generators_cubical(gen_string, dim):
     else:
         return None
 
+
 def process_generators_simplicial(gen_string, dim, complex):
     r"""
     Process CHomP generator information for simplicial complexes.
@@ -829,6 +833,7 @@ def process_generators_simplicial(gen_string, dim, complex):
     else:
         return None
 
+
 def process_generators_chain(gen_string, dim, base_ring=None):
     r"""
     Process CHomP generator information for simplicial complexes.

src/sage/interfaces/four_ti_2.py

@@ -104,7 +104,7 @@ def temp_project(self):
         n = 0
         while True:
             project = "project_%s" % n
-            touch_file = os.path.join(self.directory(),project) + '.touch'
+            touch_file = os.path.join(self.directory(), project) + '.touch'
             if not os.path.exists(touch_file):
                 break
             n += 1

src/sage/interfaces/gap_workspace.py

@@ -2,16 +2,16 @@
 Support for (lib)GAP workspace files
 """
 
-#*****************************************************************************
+# ****************************************************************************
 #       Copyright (C) 2017 Jeroen Demeyer <[email protected]>
 #                     2019 Vincent Delecroix <[email protected]>
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation, either version 2 of the License, or
 # (at your option) any later version.
-#                  http://www.gnu.org/licenses/
-#*****************************************************************************
+#                  https://www.gnu.org/licenses/
+# ****************************************************************************
 
 import os
 import time

src/sage/interfaces/gfan.py

@@ -37,7 +37,7 @@
 #
 #  The full text of the GPL is available at:
 #
-#                  http://www.gnu.org/licenses/
+#                  https://www.gnu.org/licenses/
 # *****************************************************************************
 
 from subprocess import Popen, PIPE
@@ -46,6 +46,7 @@
 
 from sage.misc.decorators import rename_keyword
 
+
 class Gfan():
     """
     Interface to Anders Jensen's Groebner Fan program.

src/sage/interfaces/gnuplot.py

@@ -2,7 +2,7 @@
 Interface to the Gnuplot interpreter
 """
 
-#*****************************************************************************
+# ****************************************************************************
 #       Copyright (C) 2005 William Stein <[email protected]>
 #
 #  Distributed under the terms of the GNU General Public License (GPL)
@@ -14,13 +14,14 @@
 #
 #  The full text of the GPL is available at:
 #
-#                  http://www.gnu.org/licenses/
-#*****************************************************************************
+#                  https://www.gnu.org/licenses/
+# ****************************************************************************
 
 import os
 import time
 from sage.structure.sage_object import SageObject
 
+
 class Gnuplot(SageObject):
     """
     Interface to the Gnuplot interpreter.
@@ -84,7 +85,7 @@ def plot(self, cmd, file=None, verbose=True, reset=True):
         if reset:
             self('reset')
         self('set terminal x11')
-        cmd = cmd.replace('^','**')
+        cmd = cmd.replace('^', '**')
         self(cmd)
         if file is not None:
             if file[-4:] == '.png':
@@ -93,7 +94,7 @@ def plot(self, cmd, file=None, verbose=True, reset=True):
                 if file[-4:] != '.eps':
                     file += '.eps'
                 self('set terminal postscript eps enhanced')
-            #self("set output '%s'"%file)
+            # self("set output '%s'"%file)
             tmp = 'gnuplot_tmp%s' % file[-4:]
             self("set output '%s'" % tmp)
             print("Saving plot to %s" % file)
@@ -109,7 +110,7 @@ def plot3d(self, f, xmin=-1, xmax=1, ymin=-1, ymax=1, zmin=-1, zmax=1,
                interact=True):
         if title is None:
             title = str(f)
-        f = f.replace('^','**')
+        f = f.replace('^', '**')
         cmd = """
         set xlabel "%s"
         set ylabel "%s"
@@ -126,7 +127,7 @@ def plot3d(self, f, xmin=-1, xmax=1, ymin=-1, ymax=1, zmin=-1, zmax=1,
         #show palette
         splot %s
         """ % (xlabel, ylabel,
-             xmin, xmax, ymin, ymax, #zmin, zmax,
+             xmin, xmax, ymin, ymax,  # zmin, zmax,
              samples, isosamples,
              title, f)
         if interact:
@@ -172,7 +173,7 @@ def plot3d_parametric(self, f='cos(u)*(3 + v*cos(u/2)), sin(u)*(3 + v*cos(u/2)),
         set pm3d; set palette; set parametric
         splot %s %s %s
         """ % (samples, title, range1, range2, f)
-        cmd = cmd.replace('^','**')
+        cmd = cmd.replace('^', '**')
         if interact:
             self.interact(cmd)
         else:

src/sage/interfaces/gp.py

@@ -136,7 +136,7 @@
 #
 #  Distributed under the terms of the GNU General Public License (GPL)
 #
-#                  http://www.gnu.org/licenses/
+#                  https://www.gnu.org/licenses/
 #
 ##########################################################################
 import os

src/sage/interfaces/interface.py

@@ -24,7 +24,7 @@
 - Simon King (2015): Improve pickling for InterfaceElement
 """
 
-#*****************************************************************************
+# ****************************************************************************
 #       Copyright (C) 2005 William Stein <[email protected]>
 #
 #  Distributed under the terms of the GNU General Public License (GPL)
@@ -37,7 +37,7 @@
 #  The full text of the GPL is available at:
 #
 #                  https://www.gnu.org/licenses/
-#*****************************************************************************
+# ****************************************************************************
 
 import operator
 
@@ -282,14 +282,14 @@ def __call__(self, x, name=None):
         """
         cls = self._object_class()
 
-        #Handle the case when x is an object
-        #in some interface.
+        # Handle the case when x is an object
+        # in some interface.
         if isinstance(x, InterfaceElement):
             if x.parent() is self:
                 return x
 
-            #We convert x into an object in this
-            #interface by first going through Sage.
+            # We convert x into an object in this
+            # interface by first going through Sage.
             try:
                 return self(x._sage_())
             except (NotImplementedError, TypeError):
@@ -471,7 +471,7 @@ def set(self, var, value):
         """
         Set the variable var to the given value.
         """
-        cmd = '%s%s%s;' % (var,self._assign_symbol(), value)
+        cmd = '%s%s%s;' % (var, self._assign_symbol(), value)
         self.eval(cmd)
 
     def get(self, var):
@@ -613,7 +613,7 @@ def function_call(self, function, args=None, kwds=None):
         self._check_valid_function_name(function)
         s = self._function_call_string(function,
                                        [s.name() for s in args],
-                                       ['%s=%s' % (key,value.name()) for key, value in kwds.items()])
+                                       ['%s=%s' % (key, value.name()) for key, value in kwds.items()])
         return self.new(s)
 
     def _function_call_string(self, function, args, kwds):
@@ -1016,7 +1016,7 @@ def __del__(self):
             self._check_valid()
         except ValueError:
             return
-        if hasattr(self,'_name'):
+        if hasattr(self, '_name'):
             P = self.parent()
             if P is not None:
                 P.clear(self._name)
@@ -1053,9 +1053,9 @@ def _sage_repr(self):
 
         - Felix Lawrence (2009-08-21)
         """
-        #TO DO: this could use file transfers when self.is_remote()
+        # TO DO: this could use file transfers when self.is_remote()
 
-        string = repr(self).replace('\n',' ').replace('\r', '')
+        string = repr(self).replace('\n', ' ').replace('\r', '')
         # Translate the external program's function notation to Sage's
         lfd = self.parent()._left_func_delim()
         if '(' != lfd:

src/sage/interfaces/magma.py

@@ -1303,33 +1303,35 @@ def _object_class(self):
     # It's very painful using the interface without this.
     def _left_list_delim(self):
         """
-        Return the left sequence delimiter in Magma. Despite the name in
-        this function, this is really the least painful choice.
+        Return the left sequence delimiter in Magma.
+
+        Despite the name in this function, this is really the least
+        painful choice.
 
         EXAMPLES::
 
             sage: magma._left_list_delim()
             '['
         """
-        #return "[*"
         return "["
 
     def _right_list_delim(self):
         """
-        Return the right sequence delimiter in Magma. Despite the name in
-        this function, this is really the least painful choice.
+        Return the right sequence delimiter in Magma.
+
+        Despite the name in this function, this is really the least
+        painful choice.
 
         EXAMPLES::
 
             sage: magma._right_list_delim()
             ']'
         """
-        #return "*]"
         return "]"
 
     def _assign_symbol(self):
         """
-        Returns the assignment symbol in Magma.
+        Return the assignment symbol in Magma.
 
         EXAMPLES::
 
@@ -1340,7 +1342,7 @@ def _assign_symbol(self):
 
     def _equality_symbol(self):
         """
-        Returns the equality testing logical symbol in Magma.
+        Return the equality testing logical symbol in Magma.
 
         EXAMPLES::
 
@@ -1351,7 +1353,7 @@ def _equality_symbol(self):
 
     def _lessthan_symbol(self):
         """
-        Returns the less than testing logical symbol in Magma.
+        Return the less than testing logical symbol in Magma.
 
         EXAMPLES::
 
@@ -1362,7 +1364,7 @@ def _lessthan_symbol(self):
 
     def _greaterthan_symbol(self):
         """
-        Returns the greater than testing logical symbol in Magma.
+        Return the greater than testing logical symbol in Magma.
 
         EXAMPLES::
 
@@ -1375,7 +1377,7 @@ def _greaterthan_symbol(self):
     # in your derived class.
     def _true_symbol(self):
         """
-        Returns the string representation of "truth" in Magma.
+        Return the string representation of "truth" in Magma.
 
         EXAMPLES::
 
@@ -1386,7 +1388,7 @@ def _true_symbol(self):
 
     def _false_symbol(self):
         """
-        Returns the string representation of "false" in Magma.
+        Return the string representation of "false" in Magma.
 
         EXAMPLES::
 
@@ -1642,6 +1644,7 @@ def get_nthreads(self):
 
     GetNthreads = get_nthreads
 
+
 @instancedoc
 class MagmaFunctionElement(FunctionElement):
     def __call__(self, *args, **kwds):