CLN: unify a ValueError message for removed units T, L, U, N and remove these entries from UnitChoices (#59119)

cln: change msg in ValueError for units T, L, U, N

Author: natmokval

pandas/_libs/tslibs/dtypes.pyx

@@ -453,10 +453,6 @@ class Resolution(Enum):
         """
         cdef:
             str abbrev
-        if freq in {"T", "t", "L", "l", "U", "u", "N", "n"}:
-            raise ValueError(
-                f"Frequency \'{freq}\' is no longer supported."
-            )
         try:
             if freq in c_DEPR_ABBREVS:
                 abbrev = c_DEPR_ABBREVS[freq]

pandas/_libs/tslibs/timedeltas.pyi

@@ -39,8 +39,6 @@ UnitChoices: TypeAlias = Literal[
     "minute",
     "min",
     "minutes",
-    "T",
-    "t",
     "s",
     "seconds",
     "sec",
@@ -50,21 +48,17 @@ UnitChoices: TypeAlias = Literal[
     "millisecond",
     "milli",
     "millis",
-    "L",
-    "l",
     "us",
     "microseconds",
     "microsecond",
     "µs",
     "micro",
     "micros",
-    "u",
     "ns",
     "nanoseconds",
     "nano",
     "nanos",
     "nanosecond",
-    "n",
 ]
 _S = TypeVar("_S", bound=timedelta)
 

pandas/_libs/tslibs/timedeltas.pyx

@@ -1818,11 +1818,6 @@ class Timedelta(_Timedelta):
         * 'microseconds', 'microsecond', 'micros', 'micro', or 'us'
         * 'nanoseconds', 'nanosecond', 'nanos', 'nano', or 'ns'.
 
-        .. deprecated:: 2.2.0
-
-            Values `H`, `T`, `S`, `L`, `U`, and `N` are deprecated in favour
-            of the values `h`, `min`, `s`, `ms`, `us`, and `ns`.
-
         .. deprecated:: 3.0.0
 
             Allowing the values `w`, `d`, `MIN`, `MS`, `US` and `NS` to denote units

pandas/tests/tslibs/test_resolution.py

@@ -56,10 +56,3 @@ def test_units_H_S_deprecated_from_attrname_to_abbrevs(freq):
 
     with tm.assert_produces_warning(FutureWarning, match=msg):
         Resolution.get_reso_from_freqstr(freq)
-
-
-@pytest.mark.parametrize("freq", ["T", "t", "L", "U", "N", "n"])
-def test_reso_abbrev_T_L_U_N_raises(freq):
-    msg = f"Frequency '{freq}' is no longer supported."
-    with pytest.raises(ValueError, match=msg):
-        Resolution.get_reso_from_freqstr(freq)