# Install and Use
## Installation
Execute the following command:
```text
pip install validators
```
> It's preferable to use `pip` within a virtual environment.
## Usage
```python
import validators
print(validators.email('someone@example.com'))
```
### To raise validation error
1. Either set the environment variable `RAISE_VALIDATION_ERROR` to `True`
```console
$ export RAISE_VALIDATION_ERROR=True
$ python -c "from validators import url; print(url('https//bad_url'))"
Traceback (most recent call last):
File "", line 1, in
File "/path/to/lib/validators/utils.py", line 87, in wrapper
raise ValidationError(func, _func_args_as_dict(func, *args, **kwargs))
validators.utils.ValidationError: ValidationError(func=url, args={'value': 'https//bad_url'})
```
2. Or pass `r_ve=True` to each caller function:
```console
$ python -c "from validators.card import visa; print(visa('bad_visa_number', r_ve=True))"
Traceback (most recent call last):
File "", line 1, in
File "/path/to/lib/validators/utils.py", line 87, in wrapper
raise ValidationError(func, _func_args_as_dict(func, *args, **kwargs))
validators.utils.ValidationError: ValidationError(func=visa, args={'value': 'bad_visa_number'})
```