How to modify python script to append data on file using sql server 2019?

Python Help
1

I need to append data to excel file already exist from table students on SQL Server .

So I need to append data when dbo.fn_FileExists(@FullFilePath)=1

Excel file already Created on D:\ExportExcel\dbo.students.xlsx with student IDs 1 and 2.

StudentId Name
1 ahmed
2 eslam

Table structure:

CREATE TABLE [dbo].[students](
    [StudentId] [int] NOT NULL,
    [Name] [varchar](50) NULL,
 CONSTRAINT [PK_students] PRIMARY KEY CLUSTERED 
(
    [StudentId] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
INSERT [dbo].[students] ([StudentId], [Name]) VALUES (3, N'Sayed')
INSERT [dbo].[students] ([StudentId], [Name]) VALUES (4, N'Michel')

Python script used

DECLARE @PythonScript NVARCHAR(MAX) = N''
  declare @SQL NVARCHAR(MAX) = N'select studentid,Name from dbo.students;'
  declare @ExportPath varchar(max)='D:\ExportExcel\'
  declare @TableName varchar(max)='dbo.students'
  declare @FullFilePath varchar(max) = concat(@ExportPath,@TableName+'.xlsx')
--IF File Not Exist
if(dbo.fn_FileExists(@FullFilePath)=0)
BEGIN
   ---print 'Create File'
SET @PythonScript = N'
FullFilePath = ExcelFilePath+TableName+".xlsx"
InputDataSet.to_excel(FullFilePath,sheet_name=TableName.split(".")[-1],index=False)'
   
EXEC   sp_execute_external_script
      @language = N'Python'
     ,@script = @PythonScript
     ,@input_data_1 = @SQL
     ,@params = N'@ExcelFilePath NVARCHAR(MAX), @TableName NVARCHAR(200)'
     ,@ExcelFilePath = @ExportPath -- file path where Excel files are placed
     ,@TableName = @TableName
END
ELSE
BEGIN
---append data
---Here code i need to write to append data
print 'Append data'
END

When use Python script it will not append data to Excel file from table students. Meaning it will not add student IDs 3 and 4 .

So How to append data from table students to excel file using Python script?

Expected result to file after append

StudentId Name
1 ahmed
2 eslam
3 Sayed
4 Michel