Deprecate some methods the should not be used anymore

And cleanup some code that had no effect/should be unused.

IPython/core/oinspect.py

@@ -76,7 +76,7 b" info_fields = ['type_name', 'base_class', 'string_form', 'namespace',"
                'call_def', 'call_docstring',
                # These won't be printed but will be used to determine how to
                # format the object
-               'ismagic', 'isalias', 'isclass', 'argspec', 'found', 'name'
+               'ismagic', 'isalias', 'isclass', 'found', 'name'
                ]
 
 
@@ -200,26 +200,39 b' def is_simple_callable(obj):'
     return (inspect.isfunction(obj) or inspect.ismethod(obj) or \
             isinstance(obj, _builtin_func_type) or isinstance(obj, _builtin_meth_type))
 
-
+@undoc
 def getargspec(obj):
     """Wrapper around :func:`inspect.getfullargspec` on Python 3, and
     :func:inspect.getargspec` on Python 2.
 
     In addition to functions and methods, this can also handle objects with a
     ``__call__`` attribute.
+
+    DEPRECATED: Deprecated since 7.10. Do not use, will be removed.
     """
+
+    warnings.warn('`getargspec` function is deprecated as of IPython 7.10'
+                  'and will be removed in future versions.', DeprecationWarning, stacklevel=2)
+
     if safe_hasattr(obj, '__call__') and not is_simple_callable(obj):
         obj = obj.__call__
 
     return inspect.getfullargspec(obj)
 
-
+@undoc
 def format_argspec(argspec):
     """Format argspect, convenience wrapper around inspect's.
 
     This takes a dict instead of ordered arguments and calls
     inspect.format_argspec with the arguments in the necessary order.
+
+    DEPRECATED: Do not use; will be removed in future versions.
     """
+    
+    warnings.warn('`format_argspec` function is deprecated as of IPython 7.10'
+                  'and will be removed in future versions.', DeprecationWarning, stacklevel=2)
+
+
     return inspect.formatargspec(argspec['args'], argspec['varargs'],
                                  argspec['varkw'], argspec['defaults'])
 
@@ -916,33 +929,6 b' class Inspector(Colorable):'
                 if call_ds:
                     out['call_docstring'] = call_ds
 
-        # Compute the object's argspec as a callable.  The key is to decide
-        # whether to pull it from the object itself, from its __init__ or
-        # from its __call__ method.
-
-        if inspect.isclass(obj):
-            # Old-style classes need not have an __init__
-            callable_obj = getattr(obj, "__init__", None)
-        elif callable(obj):
-            callable_obj = obj
-        else:
-            callable_obj = None
-
-        if callable_obj is not None:
-            try:
-                argspec = getargspec(callable_obj)
-            except Exception:
-                # For extensions/builtins we can't retrieve the argspec
-                pass
-            else:
-                # named tuples' _asdict() method returns an OrderedDict, but we
-                # we want a normal
-                out['argspec'] = argspec_dict = dict(argspec._asdict())
-                # We called this varkw before argspec became a named tuple.
-                # With getfullargspec it's also called varkw.
-                if 'varkw' not in argspec_dict:
-                    argspec_dict['varkw'] = argspec_dict.pop('keywords')
-
         return object_info(**out)
 
     @staticmethod