UnboundLocalError: local variable 'data' referenced before assignment

从 issue 中的代码开始，尤其是 outer_function 和读取 Sheet1 的循环。运行示例以复现 UnboundLocalError，然后跟踪数据被赋值和使用的路径；完成的标准是示例能够处理相关的工作表内容，而不会引用未设置的局部变量。

import xlsxwriter
import pandas as pd
import openpyxl
import pandas as pd

current=1
i = 0
counter=0

Create some Pandas dataframes from some data.

df1 = pd.DataFrame({'Data1': [11, 12, 13, 14]})
df2 = pd.DataFrame({'Data2': [21, 22, 23, 24,25]})
df3 = pd.DataFrame({'Data3': [31, 32, 33, 34,35,36]})
df4 = pd.DataFrame({'Data4': [41, 42, 43, 44,45,46,47]})
df5 = pd.DataFrame({'Data5': [51, 52, 53, 54,55,56,57,58]})

Create a Pandas Excel writer using XlsxWriter as the engine.

writer = pd.ExcelWriter('pandas_positioning.xlsx', engine='xlsxwriter')

Position the dataframes in the worksheet.

df1.to_excel(writer, sheet_name='Sheet1',startrow=0) # Default position, cell A1.
df2.to_excel(writer, sheet_name='Sheet1', startcol=0,startrow=5)
df3.to_excel(writer, sheet_name='Sheet1', startrow=0,startcol=11)
df3.to_excel(writer, sheet_name='Sheet1', startrow=0,startcol=18)
df3.to_excel(writer, sheet_name='Sheet1', startrow=0,startcol=26)

It is also possible to write the dataframe without the header and index.

#df4.to_excel(writer, sheet_name='Sheet1', startrow=7, startcol=4, header=False, index=False)

Close the Pandas Excel writer and output the Excel file.

writer.save()

def outer_function():
import xlrd
wb=xlrd.open_workbook('C:/Users/bened/pandas_positioning.xlsx')
sheet=wb.sheet_by_name('Sheet1')

for i in range(sheet.nrows):
    if(sheet.cell_value(i,0)=='Data3'):
            data=i
    d=0
    while(d<data):
        print('hi')
        break

outer_function()

how do i solve UnboundLocalError: local variable 'data' referenced before assignment