I am not getting any output in the Subset_soil_param.txt file

[Baloch]

Hello,
I am new to Python and to this forum, so I need some help with the following code:

original_soil_parameter_file = open('D:\Spring 2020\VIC\Parameter_files\original_soil_param.txt', "r")
Grid_Cell_id = open('D:\Spring 2020\VIC\Parameter_files\Grid_Cells.txt', "r")
Subset_soil_param = open('D:\Spring 2020\VIC\Parameter_files\subset_soil_param.txt', "w")
with open('D:\Spring 2020\VIC\Parameter_files\original_soil_param.txt') as f:
    for line in f:
        a = line.split(' ')
        if a[1] == Grid_Cell_id:
            Subset_soil_param.write(line)
Subset_soil_param.close()

Basically, I have an original file (named as original_soil_parameter_file), which covers the whole North Western United States. And I want to subset the file based on my research area. The original file contains rows of values with each values separated by a space. In order to subset I provided another text file to the code and called it Grid_cell_id. Then I used the for loop to match the second value (a[1]) with the values in Grid_Cell_id, so that after a finding an identical grid cell id in both files, the code will start saving the lines in the new file named Subset_soil_param.txt. After I run code, the Subset_soil_param is created but it's empty. I get the following output:

Output:
runfile('D:/Spring 2020/VIC/Parameter_files/subset_soil_param.py', wdir='D:/Spring 2020/VIC/Parameter_files')