Can you explain what Scope means in the context of PyTest and how it affects test execution?

In PyTest, the scope parameter defines the lifetime (lifecycle) of a fixture — that is, how long it will be created and used in tests.

Main scope values:

• function (default): the fixture is recreated for each test.
• class: the fixture is created once per test class.
• module: the fixture is created once per test module (file).
• package: the fixture is created once per package.
• session: the fixture is created once per test session.

For example, if a fixture has scope="module", it is initialized once before all tests in the module run and destroyed after they complete. This saves time and resources, especially if the fixture creates, for example, a database connection or server.

Example of a fixture with scope:

import pytest

@pytest.fixture(scope="module")
def db_connection():
    conn = create_connection()
    yield conn
    conn.close()

Thus, scope affects test performance and isolation, allowing control over how often resources are created and destroyed.