diff --git a/src/doc/en/reference/calculus/index.rst b/src/doc/en/reference/calculus/index.rst
index abbb408f6e9..c9a5158e522 100644
--- a/src/doc/en/reference/calculus/index.rst
+++ b/src/doc/en/reference/calculus/index.rst
@@ -53,7 +53,6 @@ Internal functionality supporting calculus
 - :doc:`sage/symbolic/function_factory`
 - :doc:`Internals of Callable Symbolic Expressions <sage/symbolic/callable>`
 - :doc:`sage/symbolic/expression_conversions`
-- :doc:`sage/symbolic/substitution_map`
 - :doc:`sage/symbolic/benchmark`
 - :doc:`sage/symbolic/random_tests`
 - :doc:`sage/symbolic/maxima_wrapper`
@@ -95,7 +94,6 @@ Internal functionality supporting calculus
    sage/calculus/var
    sage/symbolic/maxima_wrapper
    sage/symbolic/operators
-   sage/symbolic/substitution_map
    sage/symbolic/benchmark
    sage/symbolic/random_tests
 
diff --git a/src/sage/combinat/words/alphabet.py b/src/sage/combinat/words/alphabet.py
index 5d1b0d5468a..3289ad5aa1a 100644
--- a/src/sage/combinat/words/alphabet.py
+++ b/src/sage/combinat/words/alphabet.py
@@ -32,15 +32,14 @@
 #                  http://www.gnu.org/licenses/
 # ****************************************************************************
 
-from sage.categories.sets_cat import Sets
+import collections.abc
 
-from sage.sets.totally_ordered_finite_set import TotallyOrderedFiniteSet
-from sage.sets.family import Family
-
-from sage.rings.integer import Integer
+from sage.categories.sets_cat import Sets
 from sage.rings.infinity import Infinity
-
+from sage.rings.integer import Integer
+from sage.sets.family import Family
 from sage.sets.non_negative_integers import NonNegativeIntegers
+from sage.sets.totally_ordered_finite_set import TotallyOrderedFiniteSet
 
 
 set_of_letters = {
@@ -222,7 +221,7 @@ def build_alphabet(data=None, names=None, name=None):
             return IntegerRange(Integer(data))
         if isinstance(names, str):
             return TotallyOrderedFiniteSet([names + '%d' % i for i in range(data)])
-        if len(names) == data:
+        if isinstance(names, collections.abc.Sequence) and len(names) == data:
             return TotallyOrderedFiniteSet(names)
         raise ValueError("invalid value for names")
 
diff --git a/src/sage/symbolic/all.py b/src/sage/symbolic/all.py
index 399ab56e78c..b5a0883d202 100644
--- a/src/sage/symbolic/all.py
+++ b/src/sage/symbolic/all.py
@@ -1,10 +1,3 @@
-from sage.misc.lazy_import import lazy_import
-
-lazy_import("sage.symbolic.constants", "I", deprecation=(18036,
-        "import I from sage.symbolic.constants for the imaginary unit viewed as an element of SR, or from sage.rings.imaginary_unit for the element of ZZ[i]"))
-lazy_import("sage.symbolic.constants", "I", as_="i", deprecation=(18036,
-        "import I from sage.symbolic.constants for the imaginary unit viewed as an element of SR, or from sage.rings.imaginary_unit for the element of ZZ[i]"))
-
 from .ring import SR
 from .constants import (pi, e, NaN, golden_ratio, log2, euler_gamma, catalan,
                        khinchin, twinprime, mertens, glaisher)
diff --git a/src/sage/symbolic/callable.py b/src/sage/symbolic/callable.py
index dc093716a34..6db7f38745d 100644
--- a/src/sage/symbolic/callable.py
+++ b/src/sage/symbolic/callable.py
@@ -69,63 +69,6 @@
 ######################################################################
 #  Callable functions
 ######################################################################
-def is_CallableSymbolicExpressionRing(x):
-    """
-    Return ``True`` if ``x`` is a callable symbolic expression ring.
-
-    INPUT:
-
-    -  ``x`` - object
-
-    OUTPUT: bool
-
-    EXAMPLES::
-
-        sage: from sage.symbolic.callable import is_CallableSymbolicExpressionRing
-        sage: is_CallableSymbolicExpressionRing(QQ)
-        doctest:warning...
-        DeprecationWarning: is_CallableSymbolicExpressionRing is deprecated;
-        use isinstance(..., sage.rings.abc.CallableSymbolicExpressionRing instead
-        See https://github.com/sagemath/sage/issues/32665 for details.
-        False
-        sage: var('x,y,z')
-        (x, y, z)
-        sage: is_CallableSymbolicExpressionRing(CallableSymbolicExpressionRing((x,y,z)))
-        True
-    """
-    from sage.misc.superseded import deprecation
-    deprecation(32665, 'is_CallableSymbolicExpressionRing is deprecated; use isinstance(..., sage.rings.abc.CallableSymbolicExpressionRing instead')
-    return isinstance(x, CallableSymbolicExpressionRing_class)
-
-
-def is_CallableSymbolicExpression(x):
-    r"""
-    Return ``True`` if ``x`` is a callable symbolic expression.
-
-    EXAMPLES::
-
-        sage: from sage.symbolic.callable import is_CallableSymbolicExpression
-        sage: var('a x y z')
-        (a, x, y, z)
-        sage: f(x,y) = a + 2*x + 3*y + z
-        sage: is_CallableSymbolicExpression(f)
-        doctest:warning...
-        DeprecationWarning: is_CallableSymbolicExpression is deprecated;
-        use isinstance(..., Expression) and ....is_callable() instead
-        See https://github.com/sagemath/sage/issues/34215 for details.
-        True
-        sage: is_CallableSymbolicExpression(a+2*x)
-        False
-        sage: def foo(n): return n^2
-        ...
-        sage: is_CallableSymbolicExpression(foo)
-        False
-    """
-    from sage.misc.superseded import deprecation
-    deprecation(34215, 'is_CallableSymbolicExpression is deprecated; use isinstance(..., Expression) and ....is_callable() instead')
-    from sage.structure.element import Expression
-    return isinstance(x, Expression) and isinstance(x.parent(), CallableSymbolicExpressionRing_class)
-
 
 class CallableSymbolicExpressionFunctor(ConstructionFunctor):
     def __init__(self, arguments):
diff --git a/src/sage/symbolic/comparison.py b/src/sage/symbolic/comparison.py
deleted file mode 100644
index 38c23b97d6c..00000000000
--- a/src/sage/symbolic/comparison.py
+++ /dev/null
@@ -1,13 +0,0 @@
-r"""
-Comparison of Symbolic Expressions (deprecated module)
-
-This module consists only of deprecated lazy imports from
-:mod:`sage.symbolic.expression`.
-"""
-
-
-from sage.misc.lazy_import import lazy_import
-lazy_import('sage.symbolic.expression',
-            ['print_order', '_print_key', 'print_sorted', '_math_key',
-             'math_sorted', 'mixed_order', '_mixed_key', 'mixed_sorted'],
-            deprecation=32386)
diff --git a/src/sage/symbolic/constant.py b/src/sage/symbolic/constant.py
deleted file mode 100644
index 53571b8beb0..00000000000
--- a/src/sage/symbolic/constant.py
+++ /dev/null
@@ -1,10 +0,0 @@
-r"""
-Symbolic constants (deprecated module)
-
-This module consists only of deprecated lazy imports from
-:mod:`sage.symbolic.expression`.
-"""
-
-
-from sage.misc.lazy_import import lazy_import
-lazy_import('sage.symbolic.expression', 'PynacConstant', deprecation=32386)
diff --git a/src/sage/symbolic/constants_c.py b/src/sage/symbolic/constants_c.py
deleted file mode 100644
index b18d0d0eb2f..00000000000
--- a/src/sage/symbolic/constants_c.py
+++ /dev/null
@@ -1,10 +0,0 @@
-r"""
-The constant `e` (deprecated module)
-
-This module consists only of deprecated lazy imports from
-:mod:`sage.symbolic.expression`.
-"""
-
-
-from sage.misc.lazy_import import lazy_import
-lazy_import('sage.symbolic.expression', 'E', deprecation=32386)
diff --git a/src/sage/symbolic/expression.pxd b/src/sage/symbolic/expression.pxd
index 1fa578d43c3..33e352b7f3d 100644
--- a/src/sage/symbolic/expression.pxd
+++ b/src/sage/symbolic/expression.pxd
@@ -1,4 +1,3 @@
-cpdef bint is_Expression(x)
 cpdef _repr_Expression(x)
 cpdef _latex_Expression(x)
 cpdef new_Expression(parent, x)
diff --git a/src/sage/symbolic/expression.pyx b/src/sage/symbolic/expression.pyx
index 66f624141b3..20d7647d2e5 100644
--- a/src/sage/symbolic/expression.pyx
+++ b/src/sage/symbolic/expression.pyx
@@ -409,32 +409,6 @@ include "pynac_impl.pxi"
 from sage.symbolic.symbols import symbol_table, register_symbol  # used to be defined in pynac_impl
 
 
-cpdef bint is_Expression(x):
-    """
-    Return True if ``x`` is a symbolic expression.
-
-    This method is deprecated.  Use :func:`isinstance` with
-    :class:`sage.structure.element.Expression` instead.
-
-    EXAMPLES::
-
-        sage: from sage.symbolic.expression import is_Expression
-        sage: is_Expression(x)
-        doctest:warning...
-        DeprecationWarning: is_Expression is deprecated;
-        use isinstance(..., sage.structure.element.Expression) instead
-        See https://github.com/sagemath/sage/issues/32638 for details.
-        True
-        sage: is_Expression(2)
-        False
-        sage: is_Expression(SR(2))
-        True
-    """
-    from sage.misc.superseded import deprecation
-    deprecation(32638, 'is_Expression is deprecated; use isinstance(..., sage.structure.element.Expression) instead')
-    return isinstance(x, Expression)
-
-
 cpdef bint is_SymbolicEquation(x):
     """
     Return True if *x* is a symbolic equation.
@@ -6346,32 +6320,6 @@ cdef class Expression(Expression_abc):
 
     nops = number_of_operands
 
-    def __len__(self):
-        """
-        Return the number of operands of this expression.
-
-        This is deprecated; use :meth:`number_of_operands` instead.
-
-        EXAMPLES::
-
-            sage: var('a,b,c,x,y')
-            (a, b, c, x, y)
-            sage: len(a)
-            doctest:warning...
-            DeprecationWarning: using len on a symbolic expression is deprecated; use method number_of_operands instead
-            See https://github.com/sagemath/sage/issues/29738 for details.
-            0
-            sage: len((a^2 + b^2 + (x+y)^2))
-            3
-            sage: len((a^2))
-            2
-            sage: len(a*b^2*c)
-            3
-        """
-        from sage.misc.superseded import deprecation
-        deprecation(29738, "using len on a symbolic expression is deprecated; use method number_of_operands instead")
-        return self.number_of_operands()
-
     def _unpack_operands(self):
         """
         Unpack the operands of this expression converting each to a Python
diff --git a/src/sage/symbolic/getitem.py b/src/sage/symbolic/getitem.py
deleted file mode 100644
index 3ff5e400fba..00000000000
--- a/src/sage/symbolic/getitem.py
+++ /dev/null
@@ -1,12 +0,0 @@
-r"""
-Operands (deprecated module)
-
-This module consists only of deprecated lazy imports from
-:mod:`sage.symbolic.expression`.
-"""
-
-
-from sage.misc.lazy_import import lazy_import
-lazy_import('sage.symbolic.expression',
-            ['normalize_index_for_doctests', 'OperandsWrapper', 'restore_op_wrapper'],
-            deprecation=32386)
diff --git a/src/sage/symbolic/pynac_constant.py b/src/sage/symbolic/pynac_constant.py
deleted file mode 100644
index 080cc7637be..00000000000
--- a/src/sage/symbolic/pynac_constant.py
+++ /dev/null
@@ -1,18 +0,0 @@
-"""
-Wrapper around Pynac's constants
-"""
-
-# ****************************************************************************
-#       Copyright (C) 2008 William Stein <wstein@gmail.com>
-#       Copyright (C) 2008 Burcin Erocal <burcin@erocal.org>
-#       Copyright (C) 2009 Mike Hansen <mhansen@gmail.com>
-#
-# 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.
-#                  https://www.gnu.org/licenses/
-# ****************************************************************************
-
-from sage.misc.lazy_import import lazy_import
-lazy_import('sage.symbolic.expression', 'PynacConstant', deprecation=32386)
diff --git a/src/sage/symbolic/ring.pyx b/src/sage/symbolic/ring.pyx
index d45b88e24de..822eaacd30b 100644
--- a/src/sage/symbolic/ring.pyx
+++ b/src/sage/symbolic/ring.pyx
@@ -1301,33 +1301,6 @@ def the_SymbolicRing():
     return SR
 
 
-def is_SymbolicExpressionRing(R):
-    """
-    Return True if ``R`` is the symbolic expression ring.
-
-    This function is deprecated.  Instead, either use ``R is SR`` (to
-    test whether ``R`` is the unique symbolic ring ``SR``); or
-    ``isinstance`` with :class:`~sage.rings.abc.SymbolicRing`
-    (when also symbolic subrings and callable symbolic rings should
-    be accepted).
-
-    EXAMPLES::
-
-        sage: from sage.symbolic.ring import is_SymbolicExpressionRing
-        sage: is_SymbolicExpressionRing(ZZ)
-        doctest:warning...
-        DeprecationWarning: is_SymbolicExpressionRing is deprecated;
-        use "... is SR" or isinstance(..., sage.rings.abc.SymbolicRing instead
-        See https://github.com/sagemath/sage/issues/32665 for details.
-        False
-        sage: is_SymbolicExpressionRing(SR)
-        True
-    """
-    from sage.misc.superseded import deprecation
-    deprecation(32665, 'is_SymbolicExpressionRing is deprecated; use "... is SR" or isinstance(..., sage.rings.abc.SymbolicRing instead')
-    return R is SR
-
-
 def var(name, **kwds):
     """
     EXAMPLES::
diff --git a/src/sage/symbolic/series.py b/src/sage/symbolic/series.py
deleted file mode 100644
index 943631c52f2..00000000000
--- a/src/sage/symbolic/series.py
+++ /dev/null
@@ -1,10 +0,0 @@
-r"""
-Symbolic Series
-
-This module consists only of deprecated lazy imports from
-:mod:`sage.symbolic.expression`.
-"""
-
-
-from sage.misc.lazy_import import lazy_import
-lazy_import('sage.symbolic.expression', 'SymbolicSeries', deprecation=32386)
diff --git a/src/sage/symbolic/substitution_map.py b/src/sage/symbolic/substitution_map.py
deleted file mode 100644
index a883d3aecb0..00000000000
--- a/src/sage/symbolic/substitution_map.py
+++ /dev/null
@@ -1,21 +0,0 @@
-"""
-Substitution Maps
-
-This object wraps Pynac ``exmap`` objects. These encode substitutions
-of symbolic expressions. The main use of this module is to hook into
-Pynac's ``subs()`` methods and pass a wrapper for the substitution map
-back to Python.
-"""
-
-# ****************************************************************************
-#       Copyright (C) 2013 Volker Braun <vbraun.name@gmail.com>
-#
-# 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.
-#                  https://www.gnu.org/licenses/
-# ****************************************************************************
-
-from sage.misc.lazy_import import lazy_import
-lazy_import('sage.symbolic.expression', ('SubstitutionMap', 'make_map'), deprecation=32386)