使用python docx突出显示docx文件中的段落

我试图使用python docx突出显示.docx文件中的一个段落

from docx import Document
from docx.enum.text import WD_COLOR_INDEX

source_folder = 'D:/project/data2/'
f = source_folder+'test.docx'
document = Document(f)


for para in document.paragraphs:
    font1 = para.add_run().font
    font1.highlight_color = WD_COLOR_INDEX.RED
document.save(source_folder+'new.docx')

此代码应突出显示文档中的所有段落，但并非如此

from docx import Document
from docx.enum.text import WD_COLOR_INDEX

source_folder = 'D:/project/data2/'
f = source_folder+'test.docx'
document = Document(f)


for para in document.paragraphs:
    for run in para.runs:
        run.font.highlight_color = WD_COLOR_INDEX.RED
document.save(source_folder+'new.docx')