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Generate a python_source target for each file in the sources field.

You can either use this target generator or python_test_utils for test utility files like conftest.py. They behave identically, but can help to better model and keep separate test support files vs. production files.

Backend: pants.backend.python


type: Iterable[str] | None
default: None

Addresses to other targets that this target depends on, e.g. ['helloworld/subdir:lib', 'helloworld/main.py:lib', '3rdparty:reqs#django'].

This augments any dependencies inferred by Pants, such as by analyzing your imports. Use ./pants dependencies or ./pants peek on this target to get the final result.

See Targets and BUILD files and Targets and BUILD files for more about how addresses are formed, including for generated targets. You can also run ./pants list :: to find all addresses in your project, or ./pants list dir: to find all addresses defined in that directory.

If the target is in the same BUILD file, you can leave off the BUILD file path, e.g. :tgt instead of helloworld/subdir:tgt. For generated first-party addresses, use ./ for the file path, e.g. ./main.py:tgt; for all other generated targets, use :tgt#generated_name.

You may exclude dependencies by prefixing with !, e.g. ['!helloworld/subdir:lib', '!./sibling.txt']. Ignores are intended for false positives with dependency inference; otherwise, simply leave off the dependency from the BUILD file.


type: str | None
default: None

A human-readable description of the target.

Use ./pants list --documented :: to see all targets with descriptions.


type: Iterable[str] | None
default: None

The Python interpreters this code is compatible with.

Each element should be written in pip-style format, e.g. CPython==2.7.* or CPython>=3.6,<4. You can leave off CPython as a shorthand, e.g. >=2.7 will be expanded to CPython>=2.7.

Specify more than one element to OR the constraints, e.g. ['PyPy==3.7.*', 'CPython==3.7.*'] means either PyPy 3.7 or CPython 3.7.

If the field is not set, it will default to the option [python].interpreter_constraints.

See Interpreter compatibility for how these interpreter constraints are merged with the constraints of dependencies.


type: Dict[Union[str, Tuple[str, ...]], Dict[str, Any]] | None
default: None

Override the field values for generated {generated_target_name} targets.

Expects a dictionary of relative file paths and globs to a dictionary for the overrides. You may either use a string for a single path / glob, or a string tuple for multiple paths / globs. Each override is a dictionary of field names to the overridden value.

For example:
"foo.py": {"skip_pylint": True]},
"bar.py": {"skip_flake8": True]},
("foo.py", "bar.py"): {"tags": ["linter_disabled"]},

File paths and globs are relative to the BUILD file's directory. Every overridden file is validated to belong to this target's sources field.

If you'd like to override a field's value for every python_source target generated by this target, change the field directly on this target rather than using the overrides field.

You can specify the same file name in multiple keys, so long as you don't override the same field more than one time for the file.


type: str | None
default: None

The resolve from [python].resolves to use.

If not defined, will default to [python].default_resolve.

All dependencies must share the same value for their resolve field.


type: bool | None
default: None

Whether to use a sandbox when running this target. Defaults to [python].run_goal_use_sandbox.

If true, runs of this target with the run goal will copy the needed first-party sources into a temporary sandbox and run from there.

If false, runs of this target with the run goal will use the in-repo sources directly.

The former mode is more hermetic, and is closer to building and running the source as it were packaged in a pex_binary. Additionally, it may be necessary if your sources depend transitively on "generated" files which will be materialized in the sandbox in a source root, but are not in-repo.

The latter mode is similar to creating, activating, and using a virtual environment when running your files. It may also be necessary if the source being run writes files into the repo and computes their location relative to the executed files. Django's makemigrations command is an example of such a process.


type: bool
default: False
backend: pants.backend.experimental.python.lint.autoflake

If true, don't run Autoflake on this target's code.


type: bool
default: False
backend: pants.backend.python.lint.bandit

If true, don't run Bandit on this target's code.


type: bool
default: False
backend: pants.backend.python.lint.black

If true, don't run Black on this target's code.


type: bool
default: False
backend: pants.backend.python.lint.docformatter

If true, don't run Docformatter on this target's code.


type: bool
default: False
backend: pants.backend.python.lint.flake8

If true, don't run Flake8 on this target's code.


type: bool
default: False
backend: pants.backend.python.lint.isort

If true, don't run isort on this target's code.


type: bool
default: False
backend: pants.backend.python.typecheck.mypy

If true, don't run MyPy on this target's code.


type: bool
default: False
backend: pants.backend.python.lint.pylint

If true, don't run Pylint on this target's code.


type: bool
default: False
backend: pants.backend.experimental.python.lint.pyupgrade

If true, don't run pyupgrade on this target's code.


type: bool
default: False
backend: pants.backend.python.lint.yapf

If true, don't run yapf on this target's code.


type: Iterable[str] | None
default: ('*.py', '*.pyi', '!test_*.py', '!*_test.py', '!tests.py', '!conftest.py', '!test_*.pyi', '!*_test.pyi', '!tests.pyi')

A list of files and globs that belong to this target.

Paths are relative to the BUILD file's directory. You can ignore files/globs by prefixing them with !.

Example: sources=['example.py', 'new_*.py', '!old_ignore.py']


type: Iterable[str] | None
default: None

Arbitrary strings to describe a target.

For example, you may tag some test targets with 'integration_test' so that you could run ./pants --tag='integration_test' test :: to only run on targets with that tag.