Create an ubercam for the camera sequencer, delete the previous one if it exists, set its display options, move it into the cameras group, bake camera keys, and handle "EnableSteppedPreview"

ubercam.py

import maya.cmds as cmds

camera_name = 'ubercam'
cameras_group = 'Cameras'
overscan_value = 1.2
gate_color = (0.0, 0.0, 0.0)
gate_opacity = 1.0


if cmds.objExists(camera_name):
	cmds.delete(camera_name)

cmds.ubercam(camera_name)

cmds.setAttr(f'{camera_name}.overscan', overscan_value)
cmds.setAttr(f'{camera_name}.displayGateMaskColor', *gate_color)
cmds.setAttr(f'{camera_name}.displayGateMaskOpacity', gate_opacity)

# Toggle the setting
stepped_preview = cmds.optionVar(query="animationEnableSteppedPreview")

# Disable stepped preview before baking camera
cmds.optionVar(intValue=("animationEnableSteppedPreview", 0))
cmds.playbackOptions(edit=True, blockingAnim=False)

cmds.bakeResults(camera_name, t=(0,None), sampleBy=1)

# Re-enable stepped preview if it was enabled before
if stepped_preview:
    cmds.optionVar(intValue=("animationEnableSteppedPreview", 1))
    cmds.playbackOptions(edit=True, blockingAnim=True)

cmds.parent(camera_name, cameras_group)
cmds.select(camera_name)