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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def override_build_kwarg(workflow, k, v, platform=None):
 """ Override a build-kwarg for all worker builds """

    key = OrchestrateBuildPlugin.key
    # Use None to indicate an override for all platforms

    workspace = workflow.plugin_workspace.setdefault(key, {})
    override_kwargs = workspace.setdefault(WORKSPACE_KEY_OVERRIDE_KWARGS, {})
    override_kwargs.setdefault(platform, {})
    override_kwargs[platform][k] = v