PyMel / Python script for setting animation keys

I'm currently preparing some basic code samples for a trainee position. I've formatted some of my older tools that I had previously written, but feel confident about. I would very much appreciate a pair of experienced eyes to look over the code and its formatting.

It's written originally in Python 2.7, but I formatted it to work with Python 3.0.

It's a script for usage with Maya, which sets Keys for object animations in certain patterns.

import pymel.core as pm    

def createSin(attr):
    #list of keyframes to be set:
    kf = ['1', '4', '7', '10', '13']
    #add all selected objects to a list
    objList = pm.ls(selection=1)
    for obj in objList:
        # set max keyframe
        pm.setKeyframe(obj, v=1, attribute=attr, t=[kf[1]])
        # set min keyframe
        pm.setKeyframe(obj, v=-1, attribute=attr, t=[kf[3]])
        # set intersection keyframe
        pm.setKeyframe(obj, v=0, attribute=attr, t=[kf[0], kf[2], kf[4]])
        # Set the tangents for the given attribute to 'Spline'
        pm.keyTangent(obj, at=attr, itt='spline', ott='spline')


def createBump(attr):
    #list of keyframes to be set:
    kf = ['1', '4', '7', '10', '13', '16', '19', '22', '25']
    #add all selected objects to a list
    objList = pm.ls(selection=1)
    for obj in objList:
        #Set the Max KeyFrame value
        pm.setKeyframe(obj, v=1, attribute=attr, t=[kf[4]])
        #Set Transistion Key 1
        pm.setKeyframe(obj, v=.5, attribute=attr, t=[kf[5]])
        #Set x Intersection Keys
        pm.setKeyframe(obj, v=0, at=attr,
            t=[kf[0], kf[1], kf[2], kf[3], kf[6], kf[7], kf[8]])
        #Modify tangents to smooth out the curve
        pm.keyTangent(obj, at=attr, itt='spline', ott='spline', t=[kf[5]])
        pm.keyTangent(obj, at=attr, itt='flat', ott='flat', t=[kf[4]])
        pm.keyTangent(obj, at=attr, itt='flat', ott='spline', t=[kf[3]])
        pm.keyTangent(obj, at=attr, itt='spline', ott='flat', t=[kf[6]])


def createStep(attr):
    #list of keyframes to be set:
    kf = ['1', '4', '7', '10', '13', '16', '19', '22', '25']
    #add all selected objects to a list
    objList = pm.ls(selection=1)
    for obj in objList:
        #set start
        pm.setKeyframe(obj, v=0, attribute=attr, t=[kf[0]])
        #set transition
        pm.setKeyframe(obj, v=0.25, attribute=attr, t=[kf[1]])
        #set flat keys
        pm.setKeyframe(obj, v=0.5, attribute=attr,
            t=[kf[2], kf[3], kf[4], kf[5], kf[6]])
        #set transition
        pm.setKeyframe(obj, v=0.75, attribute=attr, t=[kf[7]])
        #set transition
        pm.setKeyframe(obj, v=1, attribute=attr, t=[kf[8]])
        #set min keyframe
        pm.keyTangent(obj, at=attr, itt='linear', ott='linear')


def createRamp(attr):
    #list of keyframes to be set:
    kf = ['1', '4', '7', '10', '13']
    #add all selected objects to a list
    objList = pm.ls(selection=1)
    for obj in objList:
        keyValue = 0
        for keyframe in kf:
            #set max keyframe
            pm.setKeyframe(obj, v=keyValue, attribute=attr, t=[keyframe])
            keyValue += 0.2
        pm.keyTangent(obj, at=attr, itt='linear', ott='linear')


def createBridge(attr):
    #list of keyframes to be set:
    kf = ['1', '4', '7', '10', '13', '16', '19', '22', '25']
    #add all selected objects to a list
    objList = pm.ls(selection=1)
    for obj in objList:
        #set max keyframe
        pm.setKeyframe(obj, v=1, attribute=attr, t=[kf[4], kf[5]])
        #set min keyframe
        pm.setKeyframe(obj, v=0, attribute=attr,
            t=[kf[0], kf[1], kf[2], kf[3], kf[6], kf[7], kf[8]])
        pm.keyTangent(obj, at=attr, itt='flat', ott='flat')

#create window for tools
attrList = ['translateX', 'translateY', 'translateZ',
    'rotateX', 'rotateY', 'rotateZ']
window = pm.window(widthHeight=(250, 200), title='AnimCurve Toolbox')
form = pm.formLayout()
tabs = pm.tabLayout(innerMarginWidth=5, innerMarginHeight=5)
pm.formLayout(
    form, edit=True, attachForm=(
        (tabs, 'top', 0),
        (tabs, 'left', 0),
        (tabs, 'bottom', 0),
        (tabs, 'right', 0)
        )
    )

child1 = pm.columnLayout()
for attr in attrList:
    pm.button(label=attr, command='createSin("%s")' % attr)
pm.setParent('..')

child2 = pm.columnLayout()
for attr in attrList:
    pm.button(label=attr, command='createStep("%s")' % attr)
pm.setParent('..')

child3 = pm.columnLayout()
for attr in attrList:
    pm.button(label=attr, command='createBridge("%s")' % attr)
pm.setParent('..')

child4 = pm.columnLayout()
for attr in attrList:
    pm.button(label=attr, command='createBump("%s")' % attr)
pm.setParent('..')

child5 = pm.columnLayout()
for attr in attrList:
    pm.button(label=attr, command='createRamp("%s")' % attr)
pm.setParent('..')

pm.tabLayout(tabs, edit=True,
    tabLabel=(
        (child1, 'Sin'),
        (child2, 'Step'),
        (child3, 'Bridge'),
        (child4, 'Bump'),
        (child5, 'Ramp')
        )
    )

pm.showWindow()

This is a script which is stored as a shelf button in Maya, not a script fired from a shell.