Initial pass of removing Python 2 support

This commit removes Six as a dependency for Pelican, replacing the
relevant aliases with the proper Python 3 imports. It also removes
references to Python 2 logic that did not require Six.

poetry.lock

@@ -17,15 +17,6 @@ version = "2.7.0"
 [package.dependencies]
 pytz = ">=2015.7"
 
-[[package]]
-category = "dev"
-description = "backports.functools_lru_cache"
-marker = "python_version < \"3\""
-name = "backports.functools-lru-cache"
-optional = false
-python-versions = ">=2.6"
-version = "1.5"
-
 [[package]]
 category = "dev"
 description = "Screen-scraping library"
@@ -54,24 +45,6 @@ optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 version = "0.4.1"
 
-[[package]]
-category = "dev"
-description = "Updated configparser from Python 3.7 for Python 2.6+."
-marker = "python_version < \"3.2\""
-name = "configparser"
-optional = false
-python-versions = ">=2.6"
-version = "3.7.4"
-
-[[package]]
-category = "dev"
-description = "Backports and enhancements for the contextlib module"
-marker = "python_version < \"3\""
-name = "contextlib2"
-optional = false
-python-versions = "*"
-version = "0.5.5"
-
 [[package]]
 category = "main"
 description = "Docutils -- Python Documentation Utilities"
@@ -88,20 +61,6 @@ optional = false
 python-versions = ">=2.7"
 version = "0.3"
 
-[package.dependencies]
-[package.dependencies.configparser]
-python = ">=2.7,<2.8"
-version = ">=3.5"
-
-[[package]]
-category = "dev"
-description = "Python 3.4 Enum backported to 3.3, 3.2, 3.1, 2.7, 2.6, 2.5, and 2.4"
-marker = "python_version < \"3.4\""
-name = "enum34"
-optional = false
-python-versions = "*"
-version = "1.1.6"
-
 [[package]]
 category = "main"
 description = "Standalone version of django.utils.feedgenerator"
@@ -136,22 +95,6 @@ mccabe = ">=0.6.0,<0.7.0"
 pycodestyle = ">=2.5.0,<2.6.0"
 pyflakes = ">=2.1.0,<2.2.0"
 
-[package.dependencies.configparser]
-python = "<3.2"
-version = "*"
-
-[package.dependencies.enum34]
-python = "<3.4"
-version = "*"
-
-[package.dependencies.functools32]
-python = "<3.2"
-version = "*"
-
-[package.dependencies.typing]
-python = "<3.5"
-version = "*"
-
 [[package]]
 category = "dev"
 description = "Flake8 and pylama plugin that checks the ordering of import statements."
@@ -164,28 +107,6 @@ version = "0.18.1"
 pycodestyle = "*"
 setuptools = "*"
 
-[package.dependencies.enum34]
-python = "<2.8"
-version = "*"
-
-[[package]]
-category = "dev"
-description = "Python function signatures from PEP362 for Python 2.6, 2.7 and 3.2+"
-marker = "python_version < \"3.3\""
-name = "funcsigs"
-optional = false
-python-versions = "*"
-version = "1.0.2"
-
-[[package]]
-category = "dev"
-description = "Backport of the functools module from Python 3.2.3 for use on 2.7 and PyPy."
-marker = "python_version < \"3.2\""
-name = "functools32"
-optional = false
-python-versions = "*"
-version = "3.2.3-2"
-
 [[package]]
 category = "dev"
 description = "Getting image size from png/jpeg/jpeg2000/gif file"
@@ -205,14 +126,6 @@ version = "0.18"
 [package.dependencies]
 zipp = ">=0.5"
 
-[package.dependencies.configparser]
-python = "<3"
-version = ">=3.5"
-
-[package.dependencies.contextlib2]
-python = "<3"
-version = "*"
-
 [[package]]
 category = "main"
 description = "A small but fast and easy to use stand-alone template engine written in pure python."
@@ -270,10 +183,6 @@ version = "3.0.5"
 [package.dependencies]
 six = "*"
 
-[package.dependencies.funcsigs]
-python = "<3.3"
-version = ">=1"
-
 [[package]]
 category = "dev"
 description = "Core utilities for Python packages"
@@ -362,7 +271,7 @@ description = "Python 2 and 3 compatibility utilities"
 name = "six"
 optional = false
 python-versions = ">=2.6, !=3.0.*, !=3.1.*"
-version = "1.12.0"
+version = "1.13.0"
 
 [[package]]
 category = "dev"
@@ -388,11 +297,6 @@ optional = false
 python-versions = "*"
 version = "1.9.2"
 
-[package.dependencies]
-[package.dependencies."backports.functools-lru-cache"]
-python = "<3"
-version = "*"
-
 [[package]]
 category = "dev"
 description = "Python documentation generator"
@@ -449,15 +353,6 @@ six = ">=1.0.0,<2"
 toml = ">=0.9.4"
 virtualenv = ">=14.0.0"
 
-[[package]]
-category = "dev"
-description = "Type Hints for Python"
-marker = "python_version < \"3.5\""
-name = "typing"
-optional = false
-python-versions = "*"
-version = "3.7.4"
-
 [[package]]
 category = "dev"
 description = "Filters to enhance web typography, including support for Django & Jinja templates"
@@ -497,27 +392,21 @@ version = "0.5.1"
 markdown = ["markdown"]
 
 [metadata]
-content-hash = "d22ff0db3331186ab2f809313de1f9efef1f9c708cc354eaa1638a5111404612"
-python-versions = "~2.7 || ^3.5"
+content-hash = "0163177d87dca0955d111319de9481cf2ed0ef014e63a3740ffaf32a1cf07212"
+python-versions = "^3.5"
 
 [metadata.hashes]
 alabaster = ["446438bdcca0e05bd45ea2de1668c1d9b032e1a9154c2c259092d77031ddd359", "a661d72d58e6ea8a57f7a86e37d86716863ee5e92788398526d58b26a4e4dc02"]
 babel = ["af92e6106cb7c55286b25b38ad7695f8b4efb36a90ba483d7f7a6628c46158ab", "e86135ae101e31e2c8ec20a4e0c5220f4eed12487d5cf3f78be7e98d3a57fc28"]
-"backports.functools-lru-cache" = ["9d98697f088eb1b0fa451391f91afb5e3ebde16bbdb272819fd091151fda4f1a", "f0b0e4eba956de51238e17573b7087e852dfe9854afd2e9c873f73fc0ca0a6dd"]
 beautifulsoup4 = ["034740f6cb549b4e932ae1ab975581e6103ac8f942200a0e9759065984391858", "945065979fb8529dd2f37dbb58f00b661bdbcbebf954f93b32fdf5263ef35348", "ba6d5c59906a85ac23dadfe5c88deaf3e179ef565f4898671253e50a78680718"]
 blinker = ["471aee25f3992bd325afa3772f1063dbdbbca947a041b8b89466dc00d606f8b6"]
 colorama = ["05eed71e2e327246ad6b38c540c4a3117230b19679b875190486ddd2d721422d", "f8ac84de7840f5b9c4e3347b3c1eaa50f7e49c2b07596221daec5edaabbd7c48"]
-configparser = ["8be81d89d6e7b4c0d4e44bcc525845f6da25821de80cb5e06e7e0238a2899e32", "da60d0014fd8c55eb48c1c5354352e363e2d30bbf7057e5e171a468390184c75"]
-contextlib2 = ["509f9419ee91cdd00ba34443217d5ca51f5a364a404e1dce9e8979cea969ca48", "f5260a6e679d2ff42ec91ec5252f4eeffdcf21053db9113bd0a8e4d953769c00"]
 docutils = ["02aec4bd92ab067f6ff27a38a38a41173bf01bed8f89157768c1573f53e474a6", "51e64ef2ebfb29cae1faa133b3710143496eca21c530f3f71424d77687764274", "7a4bd47eaf6596e1295ecb11361139febe29b084a87bf005bf899f9a42edc3c6"]
 entrypoints = ["589f874b313739ad35be6e0cd7efde2a4e9b6fea91edcc34e58ecbb8dbe56d19", "c70dd71abe5a8c85e55e12c19bd91ccfeec11a6e99044204511f9ed547d48451"]
-enum34 = ["2d81cbbe0e73112bdfe6ef8576f2238f2ba27dd0d55752a776c41d38b7da2850", "644837f692e5f550741432dd3f223bbb9852018674981b1664e5dc339387588a", "6bd0f6ad48ec2aa117d3d141940d484deccda84d4fcd884f5c3d93c23ecd8c79", "8ad8c4783bf61ded74527bffb48ed9b54166685e4230386a9ed9b1279e2df5b1"]
 feedgenerator = ["5ae05daa9cfa47fa406ee4744d0b7fa1c8a05a7a47ee0ad328ddf55327cfb106"]
 filelock = ["18d82244ee114f543149c66a6e0c14e9c4f8a1044b5cdaadd0f82159d6a6ff59", "929b7d63ec5b7d6b71b0fa5ac14e030b3f70b75747cef1b10da9b879fef15836"]
 flake8 = ["859996073f341f2670741b51ec1e67a01da142831aa1fdc6242dbf88dffbe661", "a796a115208f5c03b18f332f7c11729812c8c3ded6c46319c59b53efd3819da8"]
 flake8-import-order = ["90a80e46886259b9c396b578d75c749801a41ee969a235e163cfe1be7afd2543", "a28dc39545ea4606c1ac3c24e9d05c849c6e5444a50fb7e9cdd430fc94de6e92"]
-funcsigs = ["330cc27ccbf7f1e992e69fef78261dc7c6569012cf397db8d3de0234e6c937ca", "a7bb0f2cf3a3fd1ab2732cb49eba4252c2af4240442415b4abce3b87022a8f50"]
-functools32 = ["89d824aa6c358c421a234d7f9ee0bd75933a67c29588ce50aaa3acdf4d403fa0", "f6253dfbe0538ad2e387bd8fdfd9293c925d63553f5813c4e587745416501e6d"]
 imagesize = ["3f349de3eb99145973fefb7dbe38554414e5c30abd0c8e4b970a7c9d09f3a1d8", "f3832918bc3c66617f92e35f5d70729187676313caa60c187eb0f28b8fe5e3b5"]
 importlib-metadata = ["6dfd58dfe281e8d240937776065dd3624ad5469c835248219bd16cf2e12dbeb7", "cb6ee23b46173539939964df59d3d72c3e0c1b5d54b84f1d8a7e912fe43612db"]
 jinja2 = ["065c4f02ebe7f7cf559e49ee5a95fb800a9e4528727aec6f24402a5374c65013", "14dd6caf1527abb21f08f86c784eac40853ba93edb79552aa1e4b8aef1b61c7b"]
@@ -535,7 +424,7 @@ pygments = ["71e430bc85c88a430f000ac1d9b331d2407f681d6f6aec95e8bcfbc3df5b0127",
 pyparsing = ["1873c03321fc118f4e9746baf201ff990ceb915f433f23b395f5580d1840cb2a", "9b6323ef4ab914af344ba97510e966d64ba91055d6b9afa6b30799340e89cc03"]
 python-dateutil = ["7e6584c74aeed623791615e26efd690f29817a27c73085b78e4bad02493df2fb", "c89805f6f4d64db21ed966fda138f8a5ed7a4fdbc1a8ee329ce1b74e3c74da9e"]
 pytz = ["303879e36b721603cc54604edcac9d20401bdbe31e1e4fdee5b9f98d5d31dfda", "d747dd3d23d77ef44c6a3526e274af6efeb0a6f1afd5a69ba4d5be4098c8e141"]
-six = ["3350809f0555b11f552448330d0b52d5f24c91a322ea4a15ef22629740f3761c", "d16a0141ec1a18405cd4ce8b4613101da75da0e9a7aec5bdd4fa804d0e0eba73"]
+six = ["1f1b7d42e254082a9db6279deae68afb421ceba6158efa6131de7b3003ee93fd", "30f610279e8b2578cab6db20741130331735c781b56053c59c4076da27f06b66"]
 smartypants = ["8db97f7cbdf08d15b158a86037cd9e116b4cf37703d24e0419a0d64ca5808f0d"]
 snowballstemmer = ["9f3b9ffe0809d174f7047e121431acf99c89a7040f0ca84f94ba53a498e6d0c9"]
 soupsieve = ["72b5f1aea9101cf720a36bb2327ede866fd6f1a07b1e87c92a1cc18113cbc946", "e4e9c053d59795e440163733a7fec6c5972210e1790c507e4c7b051d6c5259de"]
@@ -543,7 +432,6 @@ sphinx = ["82cd2728c906be96e307b81352d3fd9fb731869234c6b835cc25e9a3dfb4b7e4", "b
 sphinx-rtd-theme = ["00cf895504a7895ee433807c62094cf1e95f065843bf3acd17037c3e9a2becd4", "728607e34d60456d736cc7991fd236afb828b21b82f956c5ea75f94c8414040a"]
 toml = ["229f81c57791a41d65e399fc06bf0848bab550a9dfd5ed66df18ce5f05e73d5c", "235682dd292d5899d361a811df37e04a8828a5b1da3115886b73cf81ebc9100e", "f1db651f9657708513243e61e6cc67d101a39bad662eaa9b5546f789338e07a3"]
 tox = ["dab0b0160dd187b654fc33d690ee1d7bf328bd5b8dc6ef3bb3cc468969c659ba", "ee35ffce74933a6c6ac10c9a0182e41763140a5a5070e21b114feca56eaccdcd"]
-typing = ["38566c558a0a94d6531012c8e917b1b8518a41e418f7f15f00e129cc80162ad3", "53765ec4f83a2b720214727e319607879fec4acde22c4fbb54fa2604e79e44ce", "84698954b4e6719e912ef9a42a2431407fe3755590831699debda6fba92aac55"]
 typogrify = ["8be4668cda434163ce229d87ca273a11922cb1614cb359970b7dc96eed13cb38"]
 unidecode = ["1d7a042116536098d05d599ef2b8616759f02985c85b4fef50c78a5aaf10822a", "2b6aab710c2a1647e928e36d69c21e76b453cd455f4e2621000e54b2a9b8cce8"]
 virtualenv = ["b7335cddd9260a3dd214b73a2521ffc09647bde3e9457fcca31dc3be3999d04a", "d28ca64c0f3f125f59cabf13e0a150e1c68e5eea60983cc4395d88c584495783"]