Misc tweaks...

mathics/builtin/numbers/algebra.py: black changes its autoformatting

mathics/builtin/numbers/numbertheory.py: some linting prefers triples quotes for docstrings

mathics/core/convert/sympy.py: use accurate location for singleton class. This reduces unnecessary sympy imports

CHANGES.rst: document recent SetEnvironment addition and GetEnvironment changes

test/builtin/numbers/__init__.py: needed if testing in this directory is done separately.

mathics/core/symbols.py

@@ -14,11 +14,7 @@
 # I put this constants here instead of inside `mathics.core.convert.sympy`
 # to avoid a circular reference. Maybe they should be in its own module.
 
-# Prefix used for Sympy variables.
-# We wan t this to be short to keep variable names short.
-# In tracing values, long names make output messy.
-sympy_symbol_prefix = "_m_"
-
+sympy_symbol_prefix = "_Mathics_User_"
 sympy_slot_prefix = "_Mathics_Slot_"
 
 

test/core/test_sympy_python_convert.py

@@ -42,10 +42,10 @@ def compare(self, mathics_expr, sympy_expr, **kwargs):
         self.compare_to_mathics(mathics_expr, sympy_expr)
 
     def testSymbol(self):
-        self.compare(Symbol("Global`x"), sympy.Symbol("_mg`x"))
+        self.compare(Symbol("Global`x"), sympy.Symbol("_Mathics_User_Global`x"))
         self.compare(
-            Symbol("_mu_x"),
-            sympy.Symbol("_mu`x"),
+            Symbol("_Mathics_User_x"),
+            sympy.Symbol("_Mathics_User_System`_Mathics_User_x"),
         )
 
     def testReal(self):