refactor: Modernize type annotations

fgmetric/metric.py

@@ -3,8 +3,7 @@
 from pathlib import Path
 from typing import Any
 from typing import Iterator
-from typing import Type
-from typing import TypeVar
+from typing import Self
 
 from pydantic import BaseModel
 from pydantic import model_validator
@@ -13,8 +12,6 @@
 from fgmetric.collections import CounterPivotTable
 from fgmetric.collections import DelimitedList
 
-T = TypeVar("T", bound="Metric")
-
 
 class Metric(
     DelimitedList,
@@ -59,7 +56,7 @@ class AlignmentMetric(Metric):
     """
 
     @classmethod
-    def read(cls: Type[T], path: Path, delimiter: str = "\t") -> Iterator[T]:
+    def read(cls, path: Path, delimiter: str = "\t") -> Iterator[Self]:
         """Read Metric instances from file."""
         # NOTE: the utf-8-sig encoding is required to auto-remove BOM from input file headers
         with path.open(encoding="utf-8-sig") as fin:

fgmetric/metric_writer.py

@@ -4,7 +4,7 @@
 from pathlib import Path
 from types import TracebackType
 from typing import Iterable
-from typing import Type
+from typing import Self
 
 from fgmetric.metric import Metric
 
@@ -43,7 +43,7 @@ class AlignmentMetric(Metric):
 
     _metric_class: type[T]
     _fout: TextIOWrapper
-    _writer: DictWriter
+    _writer: DictWriter[str]
 
     def __init__(
         self,
@@ -77,12 +77,12 @@ def __init__(
             self._fout.close()
             raise
 
-    def __enter__(self) -> "MetricWriter":
+    def __enter__(self) -> Self:
         return self
 
     def __exit__(
         self,
-        exc_type: Type[BaseException] | None = None,
+        exc_type: type[BaseException] | None = None,
         exc_value: BaseException | None = None,
         traceback: TracebackType | None = None,
     ) -> None: