Please use FileSystem tools to finish the following task:

Please help me identify duplicate names from the list of all the 150 students. Do not use python code. Then generate a `namesake.txt` file to record the results in the following format, with each group written in three lines:

name: xxx
count: xxx
ids: xxx, xxx, ...

Leave one blank line between every two groups. If there are multiple duplicates, just list all corresponding IDs in the third line.
