fix test: simplify check sqlite3 module not imported if not used.

Author: schettino72

tests/test_dependency.py

@@ -40,14 +40,8 @@ def test_sqlite_import():
     """
     Checks that SQLite module is not imported until the SQLite class is instantiated
     """
-    filename = os.path.join(tempfile.gettempdir(), str(uuid.uuid4()))
-
-    assert 'sqlite3' not in sys.modules
-    db = SqliteDB(filename, JSONCodec())
-    db.dump()
-    assert 'sqlite3' in sys.modules
-
-    os.remove(filename)
+    from doit import dependency
+    assert not hasattr(dependency, 'sqlite3')
 
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 # dependencies are files only (not other tasks).