human
Complete the below
@click.command(u'build-docs')
@pass_context
@click.argument(u'app')
@click.option(u'--docs-version', default=u'current')
@click.option(u'--target', default=None)
@click.option(u'--local', default=False, is_flag=True, help=u'Run    app    locally')
@click.option(u'--watch', default=False, is_flag=True, help=u'Watch    for    changes    and    rewrite')
def build_docs(context, app, docs_version=u'current', target=None, local=False, watch=False):

    ''''Setup docs in target folder of target app'
    '''

Give me a the Python program you requested?
assistant
#Here is the Python program you requested.
    from frappe.utils import watch as start_watch
    from frappe.utils.setup_docs import add_breadcrumbs_tag
    for site in context.sites:
        _build_docs_once(site, app, docs_version, target, local)
        if watch:
            def trigger_make(source_path, event_type):
                if (u'/docs/user/' in source_path):
                    target_path = frappe.get_app_path(target, u'www', u'docs', u'user', os.path.relpath(source_path, start=frappe.get_app_path(app, u'docs', u'user')))
                    shutil.copy(source_path, target_path)
                    add_breadcrumbs_tag(target_path)
                if source_path.endswith(u'/docs/index.md'):
                    target_path = frappe.get_app_path(target, u'www', u'docs', u'index.md')
                    shutil.copy(source_path, target_path)
            apps_path = frappe.get_app_path(app)
            start_watch(apps_path, handler=trigger_make)