diff --git a/mathics/builtin/box/graphics3d.py b/mathics/builtin/box/graphics3d.py
index df8b53c67..03f3ac8ec 100644
--- a/mathics/builtin/box/graphics3d.py
+++ b/mathics/builtin/box/graphics3d.py
@@ -2,8 +2,6 @@
 """
 Boxing Symbols for 3D Graphics
 """
-# Docs are not yet ready for prime time. Maybe after release 6.0.0.
-no_doc = True
 
 import json
 import numbers
@@ -27,6 +25,9 @@
 from mathics.core.symbols import Symbol, SymbolTrue
 from mathics.eval.nevaluator import eval_N
 
+# Docs are not yet ready for prime time. Maybe after release 7.0.0.
+no_doc = True
+
 
 class Graphics3DBox(GraphicsBox):
     """
diff --git a/mathics/core/evaluation.py b/mathics/core/evaluation.py
index a45b172f3..af4401a7e 100644
--- a/mathics/core/evaluation.py
+++ b/mathics/core/evaluation.py
@@ -471,7 +471,7 @@ def message(self, symbol_name: str, tag, *msgs) -> "Message":
         symbol_shortname = self.definitions.shorten_name(symbol)
 
         if settings.DEBUG_PRINT:
-            print("MESSAGE: %s::%s (%s)" % (symbol_shortname, tag, msgs))
+            print(f"MESSAGE: {symbol_shortname}::{tag} ({msgs})")
 
         text = self.definitions.get_value(symbol, "System`Messages", pattern, self)
         if text is None:
@@ -481,7 +481,7 @@ def message(self, symbol_name: str, tag, *msgs) -> "Message":
             )
 
         if text is None:
-            text = String("Message %s::%s not found." % (symbol_shortname, tag))
+            text = String(f"Message {symbol_shortname}::{tag} not found.")
 
         text = self.format_output(
             Expression(SymbolStringForm, text, *(from_python(arg) for arg in msgs)),
@@ -587,8 +587,9 @@ def __init__(self, symbol: Union[Symbol, str], tag: str, text: str) -> None:
                 use a string.
         tag: a short slug string that indicates the kind of message
 
-        In Django we need to use a string for symbol, since we need something that is JSON serializable
-        and a Mathics3 Symbol is not like this.
+        In Django we need to use a string for symbol, since we need
+        something that is JSON serializable and a Mathics3 Symbol is not
+        like this.
         """
         super(Message, self).__init__()
         self.is_message = True  # Why do we need this?
@@ -607,7 +608,7 @@ def get_data(self):
             "message": True,
             "symbol": self.symbol,
             "tag": self.tag,
-            "prefix": "%s::%s" % (self.symbol, self.tag),
+            "prefix": f"{self.symbol}::{self.tag}",
             "text": self.text,
         }
 
diff --git a/mathics/core/exceptions.py b/mathics/core/exceptions.py
index 06a0e2ff3..e1c7cb179 100644
--- a/mathics/core/exceptions.py
+++ b/mathics/core/exceptions.py
@@ -1,4 +1,7 @@
 # -*- coding: utf-8 -*-
+"""
+Various Exception objects used in Mathics3.
+"""
 
 
 class BoxExpressionError(Exception):
@@ -35,4 +38,7 @@ def __init__(self, *message):
         self._message = message
 
     def message(self, evaluation):
+        """
+        Transfer this exception to evaluation's ``message`` method.
+        """
         evaluation.message(*self._message)
diff --git a/requirements-full.txt b/requirements-full.txt
index 4514496f2..529cc51b7 100644
--- a/requirements-full.txt
+++ b/requirements-full.txt
@@ -5,4 +5,4 @@ psutil # SystemMemory and MemoryAvailable
 pyocr # Used for TextRecognize
 scikit-image >= 0.17 # FindMinimum can use this; used by Image as well
 unidecode # Used in Transliterate
-wordcloud # Used in builtin/image.py by WordCloud()
+wordcloud >= 1.9.3 # Used in builtin/image.py by WordCloud(). Previous versions assume "image.textsize" which no longer exists