I need help understanding what this code does, line by line. for file in id_list: com_df_list=[] subfolders = [f.path for f in os.scandir(source_dir) if f.is_dir() ] for dirr in subfolders: file_loc =...

I need help understanding what this code does, line by line.

for file in id_list:

com_df_list=[]
subfolders = [f.path for f in os.scandir(source_dir) if f.is_dir() ]

for dirr in subfolders:
file_loc = dirr +"/"+ file.strip()+input_end
# print(file_loc)
df = pd.read_csv(file_loc)

com_df_list.append(df)