Log Message:
py-stripe: updated to 2.18.0

2.18.0:
* Add configurable telemetry to gather information on client-side request latency

2.17.0:
* Add support for Checkout sessions

2.16.0:
* Add support for account links

2.15.0:
* Add support for providing custom CA certificate bundle

2.14.0:
* Add support for Review for Radar

2.13.0:
* Add support for ValueList and ValueListItem for Radar

2.12.1:
* Make StripeResponse a new-style class

2.12.0:
* Add new API endpoints for the Invoice resource.

2.11.1:
* Bump minimum requests version to 2.20.0 (for \ 
[CVE-2018-18074](https://nvd.nist.gov/vuln/detail/CVE-2018-18074))

2.11.0:
* Add support for the Person resource
* Add support for the WebhookEndpoint resource

2.10.1:
* Correct behavior of stripe.max_network_retries if it's reset after initial use

2.10.0:
* Add support for Stripe Terminal

2.9.0:
* Rename FileUpload to File

2.8.1:
* Don't URL-encode square brackets
* Integer-index encode all arrays

2.8.0:
* Add support for automatic network retries

2.7.0:
* Add support for reporting resources

2.6.0:
* Add support for usage record summaries

2.5.0:
* Remove unsupported Bitcoin endpoints (this is technically a breaking change, \ 
but we're releasing as a minor version because none of these APIs were usable \ 
anyway)

2.4.0:
* Add cancel support for topups
* Add support for file links

2.3.0:
* Add support for Sigma scheduled query run objects

2.2.0:
* Add support for Stripe Issuing

2.1.0:
* Add InvoiceLineItem class

2.0.3:
* Internal improvements to ApiResource.class_url

2.0.2:
* Avoid duplicate dependency on requests with Python 2.7

2.0.1:
* Fix setup.py

2.0.0:
Major version release. List of backwards incompatible changes to watch out for:
* The minimum Python versions are now 2.7 / 3.4. If you're using Python 2.6 or \ 
3.3, consider upgrading to a more recent version.
* Stripe exception classes should now be accessed via stripe.error rather than \ 
just stripe
* Some older deprecated methods have been removed
* Trying to detach an unattached source will now raise a \ 
stripe.error.InvalidRequestError exception instead of a NotImplementedError \ 
exception

Pull requests included in this release:
* Drop support for Python 2.6 and 3.3
* Use py.test for tests
* Remove deprecated code
* Remove util.json and use json module directly everywhere
* Update setup.py and test flow
* Use pipenv
* Change exception when detaching unattached sources from NotImplementedError to \ 
stripe.error.InvalidRequestError