Make a ciclic "Simple deform" Modifier property Python:

My brain go crazy: i make that script , by a button make new modifier to many objects, and here everything works, then i make 5 keyframe, now i whant make this keyframe in loop with f-curve modifier (‘CYCLES’) but i can not do it-

I would also like to understand how to remove all keyframes with a single command, or the f-curve.

for scene in bpy.data.scenes:

###some and if statement...

for object in scene.objects:

bend = object.modifiers.new(name="bend", type='SIMPLE_DEFORM')
bend.deform_method = 'BEND'
bend.angle = 0
bend.keyframe_insert('angle',frame= 0)
bend.angle = -0.05
bend.keyframe_insert('angle',frame= 30)
bend.angle = 0
bend.keyframe_insert('angle',frame= 60)
bend.angle = 0.05
bend.keyframe_insert('angle',frame= 90)
bend.angle = 0
bend.keyframe_insert('angle',frame= 120)
###bend.angle.graph.fmodifier_add(type='CYCLES')###