[fix & refactor] no more main.py, lazy_import in __init__.py

Author: p1-dta

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "lazimp"
-version = "0.0.1"
+version = "0.0.2"
 authors = [
     { name = "Dorian Turba", email = "dturba.pro@protonmail.com" },
 ]
@@ -15,7 +15,7 @@ classifiers = [
     "Programming Language :: Python :: 3",
     "License :: OSI Approved :: MIT License",
     "Operating System :: OS Independent",
-    "Development Status :: 2 - Pre-Alpha",
+    "Development Status :: 3 - Alpha",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
 ]

src/lazimp/__init__.py

@@ -1 +1,31 @@
+import collections.abc
 
+
+def lazy_import(
+        bare_import: collections.abc.Container | None = None,
+        sub_import: collections.abc.Mapping[str, str | None] | None = None,
+):
+    if bare_import is None:
+        bare_import = set()
+    if sub_import is None:
+        sub_import = {}
+
+    import functools
+    import importlib
+
+    @functools.cache
+    def getattr_(name: str):
+        if name not in bare_import and name not in sub_import:
+            raise AttributeError(
+                f'module {__name__!r} has no attribute {name!r}'
+            ) from None
+
+        try:
+            return importlib.import_module(f'.{name}',
+                                           sub_import.get(name, str))
+        except ModuleNotFoundError:
+            raise AttributeError(
+                f'module {__name__!r} has no attribute {name!r}'
+            ) from None
+
+    return getattr_