✨ Add support for Decimal fields from Pydantic and SQLAlchemy (#103)

Co-authored-by: Sebastián Ramírez <tiangolo@gmail.com>

tests/test_advanced/test_decimal/test_tutorial001.py

@@ -0,0 +1,44 @@
+from decimal import Decimal
+from unittest.mock import patch
+
+from sqlmodel import create_engine
+
+from ...conftest import get_testing_print_function
+
+expected_calls = [
+    [
+        "Hero 1:",
+        {
+            "name": "Deadpond",
+            "age": None,
+            "id": 1,
+            "secret_name": "Dive Wilson",
+            "money": Decimal("1.100"),
+        },
+    ],
+    [
+        "Hero 2:",
+        {
+            "name": "Rusty-Man",
+            "age": 48,
+            "id": 3,
+            "secret_name": "Tommy Sharp",
+            "money": Decimal("2.200"),
+        },
+    ],
+    ["Total money: 3.300"],
+]
+
+
+def test_tutorial(clear_sqlmodel):
+    from docs_src.advanced.decimal import tutorial001 as mod
+
+    mod.sqlite_url = "sqlite://"
+    mod.engine = create_engine(mod.sqlite_url)
+    calls = []
+
+    new_print = get_testing_print_function(calls)
+
+    with patch("builtins.print", new=new_print):
+        mod.main()
+    assert calls == expected_calls