b = hou.node('/obj/box1')
t = hou.parmTuple('/obj/box1/t')
tx = t[0]
tx_keyFrames = tx.keyframes()

tx_keyFrames
(<hou.Keyframe t=0 expr='bezier()' lang=exprLanguage.Hscript v=0 s=0 auto_slopes
=True a=0.333333 use_accel_ratio=True>, <hou.Keyframe t=1 expr='bezier()' lang=e
xprLanguage.Hscript v=2.36562 s=2.00002 auto_slopes=True in a=0.745363 out a=1.4
6588 use_accel_ratio=True>, <hou.Keyframe t=2.96667 expr='bezier()' lang=exprLan
guage.Hscript v=5.47767 s=0 auto_slopes=True in a=0.655556 out a=0.333333 use_ac
cel_ratio=True>)

def offsetKeyframes():
    '''Code for offsetting all keyframed parms of a selected node. Version 1.0 beta. For the Houdini community By SWest 2023'''
    inputs_validated = True

    
    selected_nodes = hou.selectedNodes()
    if selected_nodes == ():
        inputs_validated = False        
    if not inputs_validated:
        message='This tool will offset all scoped keyframes for a node. Please select a node with keyframes and try again. '
        hou.ui.displayMessage(message)    


    if(inputs_validated):
        message = 'Please type a positive or negative number for frame offset. Example -10 or 15.5'
        offset = hou.ui.readInput(message, buttons=('OK',), severity=hou.severityType.Message, default_choice=0, close_choice=-1, help=None, title=None, initial_contents=None) 
        try:
            offset = float(offset[1])
        except:
            print('There was an error with the input number.')
            inputs_validated = False

            
    if(inputs_validated):
        for node in selected_nodes:
            for parm in node.allParms():
                parm_is_scoped = parm.isScoped()
                parm_keyframes_length = 0
                try:
                    parm_keyframes = parm.keyframes()
                except:
                    continue
                else:
                    parm_keyframes_length=len(parm_keyframes)
                if(parm_keyframes_length > 0 and parm_is_scoped):
                    print(parm.path())
                    for i in range(0,parm_keyframes_length):
                        keyframe_dict=parm.keyframes()[i].asJSON(save_keys_in_frames=True)
                        frame_in=keyframe_dict['frame']
                        frame_out=frame_in+offset
                        keyframe_dict['frame'] = frame_out
                        keyframe_out = hou.Keyframe()
                        keyframe_out.fromJSON(keyframe_dict)
                        parm.setKeyframe(keyframe_out)
                        parm.deleteKeyframeAtFrame(frame_in)
    
                       
offsetKeyframes()

import hou

res = hou.ui.readInput("Frames to shift after current frame", buttons=("OK", "Cancel"))

if res[0] == 0:
    nodes=hou.node("/obj").allSubChildren()
    cframe=hou.frame()

    shift=int(res[1])
    
    animNodes=[]
    for item in nodes:
        for p in item.parms():
            if len(p.keyframes())>1:
                
                if not item in animNodes:
                    animNodes.append(item)
                    
    with hou.undos.group("Shift Keyframes"):                
        for item in animNodes:        
            print item.path()
            hou.hscript( "chkeymv -r "+item.path()+"/* "+str(cframe)+" 20000 "+str(cframe+shift)+" "+str(20000+shift) )

Traceback (most recent call last):
  File "OffsetKeyFrames", line 47, in <module>
  File "OffsetKeyFrames", line 38, in offsetKeyframes
IndexError: tuple index out of range

Line 38: keyframe_dict=parm.keyframes()[i].asJSON(save_keys_in_frames=True)

import hou

#for debugging, can be omitted when used as shelf tool as that will populate the kwargs dict for us
if not "kwargs" in globals().keys():
    kwargs={}
    kwargs["shiftclick"]=False
    

res = hou.ui.readInput("Frames to shift keyframes after current frame", buttons=("OK", "Cancel"))

if res[0] == 0 and res[1].replace("-","").isnumeric():
    currentFrame=hou.frame()
    shift= int(res[1])
    with hou.undos.group("Shift Keyframes"):                
        list(map(lambda animObj:  hou.hscript( "chkeymv -r "+animObj.path()+"/* "+str(currentFrame)+" 20000 "+str(currentFrame+shift)+" "+str(20000+shift) ),  list(filter(lambda  node:  len(list(filter(lambda parm: len(parm.keyframes())>1, node.parms() ))), hou.node("/" if kwargs["shiftclick"] else "/obj").allSubChildren() )))) 

# this gets all nodes from /obj or /  (every context) depending on shiftclick or not:   
# hou.node("/" if kwargs["shiftclick"] else "/obj").allSubChildren()

# This filters the nodes from the above list to those that have parms that have more then 1 keyframe (parms with expression have a keyframe as well, and 1 keyframe parms are not animated since it will yield a contant value thus only focus on those with more then 1 keyframe):
# list(filter(lambda  node:  len(list(filter(lambda parm: len(parm.keyframes())>1, node.parms() )))

# The 'map' function then runs each node from that filtered list through a small lambda function that sets up and executes the hscript command 'chkeymv' with the correct settings:
# map(lambda animObj:  hou.hscript( "chkeymv -r "+animObj.path()+"/* "+str(currentFrame)+" 20000 "+str(currentFrame+shift)+" "+str(20000+shift) )

# The map function creates an iterator object that doesn't loop over all the items by itself so we force it to yield by converting it into a list. The generated list itself isn't used

Line 38: keyframe_dict=parm.keyframes()[i].asJSON(save_keys_in_frames=True)