* Force reinstall of setuptools to 49.6.0 (#1962)

* try updating in virtualenv

* new cache

* am i using 39.0.1 and if so why is it failing?

* somewhere somehow we are upgrading to setuptools 50.0.3... but where..?

* looks like somewhere between setup + pipenv-install we get a newer version of setuptools

* looks like somewhere between setup + pipenv-install we get a newer version of setuptools

* force reinstall

* looks like it's test requirements messing us up?

* force reinstall + cleanup debugs

* Fix up dg._block() to be dg.container()

* Add a unit test

* Add an e2e test for st.container

* Minor cleanups

* Clean up variable names and comments

* Clean up deltaPath code and docs

* Organize DGs in a tree, to track the `with DG`

* Enable `with` in every st.foo call

* Appease mypy with # type: ignore

* More sacrifices at the altar of mypy

* Add unit and e2e tests for with

* Actually, don't rely on each DG mixin to call _active_dg

Revert "Appease mypy with # type: ignore"

This reverts commit 4ba7c47.

Revert "Enable `with` in every st.foo call"

This reverts commit 9b467d6.

* Use the active DG for all "protected" class methods

* Clean up DG docs

* Don't switch DGs from add_rows

Per Karrie's suggestion

Co-authored-by: karrie <[email protected]>

* develop:
  Migrate Modal to Baseweb (streamlit#1930)
  Update bl dependency to resolve CVE (streamlit#1965)
  Force reinstall of setuptools to 49.6.0 (streamlit#1962)
  ComponentInstance unit tests (streamlit#1956)
  Update change log
  Fix alignment of `.. output::` command in st.write() (streamlit#1955)
  Fix alignment of `.. output::` command in st.write() (streamlit#1955)
  Add spacing to slider docs
  Up version to 0.66.0
  Switch statement to include ArrowTable (streamlit#1951)
  Remove st.write from unsupported in sidebar (streamlit#1952)
  Remove st.write from unsupported in sidebar (streamlit#1952)
  Switch statement to include ArrowTable (streamlit#1951)
  Add deprecation label to st.deck_gl_chart (streamlit#1943)
  Pin setuptools to <= 49.6.0 (streamlit#1944)
  DuplicateWidgetID error message should surface widget name (streamlit#1942)
  Set z-index of balloons to 1000000 to allow it to display over other elements. (streamlit#1934)

* [Horizontal Layout] Implement st.container() (#1961)

* Fix up dg._block() to be dg.container()

* Add a unit test

* Add an e2e test for st.container

* Minor cleanups

* Clean up variable names and comments

* Clean up deltaPath code and docs

* [Horizontal Layout] Implement `with DG` (#1964)

* Force reinstall of setuptools to 49.6.0 (#1962)

* try updating in virtualenv

* new cache

* am i using 39.0.1 and if so why is it failing?

* somewhere somehow we are upgrading to setuptools 50.0.3... but where..?

* looks like somewhere between setup + pipenv-install we get a newer version of setuptools

* looks like somewhere between setup + pipenv-install we get a newer version of setuptools

* force reinstall

* looks like it's test requirements messing us up?

* force reinstall + cleanup debugs

* Fix up dg._block() to be dg.container()

* Add a unit test

* Add an e2e test for st.container

* Minor cleanups

* Clean up variable names and comments

* Clean up deltaPath code and docs

* Organize DGs in a tree, to track the `with DG`

* Enable `with` in every st.foo call

* Appease mypy with # type: ignore

* More sacrifices at the altar of mypy

* Add unit and e2e tests for with

* Actually, don't rely on each DG mixin to call _active_dg

Revert "Appease mypy with # type: ignore"

This reverts commit 4ba7c47.

Revert "Enable `with` in every st.foo call"

This reverts commit 9b467d6.

* Use the active DG for all "protected" class methods

* Clean up DG docs

* Don't switch DGs from add_rows

Per Karrie's suggestion

Co-authored-by: karrie <[email protected]>

* [horiz-layout] Add collapsible_container (#1978)

* Add collapsible_container

* Add default collapsed

* make label required + initial docs

* Consolidate with WIP column work

* Address PR comments for more cleanliness

* Update e2e tests

* Rename collapsible container (#1993)

* rename to expander

* Fix tests

* Rename collapsible to expandable

* [Horiz Layout] Columns (#1979)

* Implement columns with variable widths

* Add a e2e test for columns

* Add a unit test

* Update Prettier to 1.19 to allow optional chaining

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Optional_chaining

* Fix e2e test

* Downgrade Prettier back to 1.18

* Empty columns now take up space

* Remove duplicate function from merge conflict

* Use flex-gap instead of margin, so column sides don't get padded

* Minor tweaks requested by code review

* Prefix new layout methods with `beta_`

Co-authored-by: karrie <[email protected]>