Why are generic arguments described by `T@function_name` by pyright?

Question

Given the following block of code:

import typing as tp

T = tp.TypeVar("T")

def dummy(item: T) -> T:
    return item

reveal_type(dummy)

When run onto it, pyright prints:

❯ pyright type_arobase.py
< some output trimmed >
/home/gregoire.roussel/dev/wdc/python/type_arobase.py
  /home/gregoire.roussel/dev/wdc/python/type_arobase.py:8:13 - information: Type of "dummy" is "(item: T@dummy) -> T@dummy"
0 errors, 0 warnings, 1 information 
Completed in 0.617sec

Note the T@dummy in the output.

• Why does pyright feel the need to suffix all generic types with a @function_name ?
• What additional information does it bring compared to the original signature (item: T) -> T ?

Note: I found in the pyright doc this paragraph that mentions this phenomenon in the special case of self and cls argument, without more details.