格式化 Dataframe 后，我无法用空白替换nan。在最后一步中，我在哪里/如何应用fillna（''）？

col_format = {'2021 Unique Members':'{:,.0f}', '2022 Unique Members':'{:,.0f}', '2021 Total Visits':'{:,.0f}',
            '2022 Total Visits':'{:,.0f}', '2022 Annualized Unique Members':'{:,.0f}', '2022 Annualized Total Visits':'{:,.0f}',
            'Anticipated Member % Increase*':'{:,.2%}', 'Anticipated Visit % Increase*':'{:,.2%}', 'Visits per Unique Member**':'{:,.2f}'}

       
df_wide_styled = df_wide.style.\
    format(col_format).\
    hide(axis='index').\
    set_caption('Behavioral Health Vendor Utilization').\
    set_table_styles(   
    [{'selector': 'th',
      'props': [('background', '#78BE20'), ('color', 'black'), ('font-weight', 'bold'), ('text-align', 'center'), ('max-width', '140px')]},
     {'selector': 'th.row_heading',
     'props': [('background', 'white'), ('color', 'black'),('font-weight', 'bold') ]},
     {'selector': 'caption',
    'props': [('color', 'Black'), ('font-size', '18px'), ('text-align','center'), ('border', '1px black solid !important')]}
    ]
    ).\
    set_properties(**{'text-align': 'center'}).\

如果“Styer”没有属性“fillna”，则会抛出错误