Note commutativity of Equal Uneqal UnsameQ in docs

Go over docs to remove extraneous and sometimes wrong information.

Lint code

Author: rocky

mathics/builtin/comparison.py

@@ -3,7 +3,7 @@
 
 from mathics.version import __version__  # noqa used in loading to check consistency.
 
-from typing import Optional, Union
+from typing import Optional
 
 import sympy
 
@@ -16,7 +16,6 @@
 from mathics.builtin.constants import mp_convert_constant
 
 from mathics.core.expression import (
-    Atom,
     COMPARE_PREC,
     Complex,
     Expression,
@@ -44,9 +43,10 @@ def is_number(sympy_value) -> bool:
 class SameQ(BinaryOperator):
     """
     <dl>
-    <dt>'SameQ[$x$, $y$]'
-    <dt>'$x$ === $y$'
-        <dd>returns 'True' if $x$ and $y$ are structurally identical.
+      <dt>'SameQ[$x$, $y$]'
+      <dt>'$x$ === $y$'
+      <dd>returns 'True' if $x$ and $y$ are structurally identical.
+      Commutative properties apply, so if $x$ === $y$ then $y$ === $x$.
     </dl>
 
     Any object is the same as itself:
@@ -74,9 +74,10 @@ def apply(self, lhs, rhs, evaluation):
 class UnsameQ(BinaryOperator):
     """
     <dl>
-    <dt>'UnsameQ[$x$, $y$]'
-    <dt>'$x$ =!= $y$'
-        <dd>returns 'True' if $x$ and $y$ are not structurally identical.
+      <dt>'UnsameQ[$x$, $y$]'
+      <dt>'$x$ =!= $y$'
+      <dd>returns 'True' if $x$ and $y$ are not structurally identical.
+      Commutative properties apply, so if $x$ =!= $y$, then $y$ =!= $x$.
     </dl>
 
     >> a=!=a
@@ -528,12 +529,12 @@ def pairs(items):
 class Equal(_EqualityOperator, SympyComparison):
     """
     <dl>
-    <dt>'Equal[$x$, $y$]'
+      <dt>'Equal[$x$, $y$]'
       <dt>'$x$ == $y$'
-      <dd>yields 'True' if $x$ and $y$ are known to be equal, or
-        'False' if $x$ and $y$ are known to be unequal.
-    <dt>'$lhs$ == $rhs$'
-        <dd>represents the equation $lhs$ = $rhs$.
+      <dd>is 'True' if $x$ and $y$ are known to be equal, or
+        'False' if $x$ and $y$ are known to be unequal, in which case
+        case, 'Not[$x$ == $y$]' will be 'True'.
+        Commutative properties apply, so if $x$ === $y$ then $y$ === $x$.
     </dl>
 
     >> a==a
@@ -638,12 +639,12 @@ def _op(x):
 class Unequal(_EqualityOperator, SympyComparison):
     """
     <dl>
-    <dt>'Unequal[$x$, $y$]'
-    <dt>'$x$ != $y$'
-        <dd>yields 'False' if $x$ and $y$ are known to be equal, or
+      <dt>'Unequal[$x$, $y$]'
+      <dt>'$x$ != $y$'
+      <dd>is 'False' if $x$ and $y$ are known to be equal, or
         'True' if $x$ and $y$ are known to be unequal.
-    <dt>'$lhs$ == $rhs$'
-        <dd>represents the inequality $lhs$   $rhs$.
+        Commutative properties apply so if $x$ != $y$ then
+        $y$ != $x$.
     </dl>
 
     >> 1 != 1.

mathics/builtin/files.py

@@ -2252,6 +2252,9 @@ class Get(PrefixOperator):
     <dl>
       <dt>'<<$name$'
       <dd>reads a file and evaluates each expression, returning only the last one.
+
+      <dt>'Get[$name$, Trace->True]'
+      <dd>Runs Get tracing each line before it is evaluated.
     </dl>
 
     S> filename = $TemporaryDirectory <> "/example_file";