py-textual: Added package py-textual (#42291)

* py-textual: New package py-textual

* py-textual: Depend on py-mdit-py-plugins

* py-textual: Added dependency on python@3.8:3

* py-textual: Added a comment about why there is a dependency on
py-mdit-py-plugins

* py-textual: Ran black

---------

Co-authored-by: Alex C Leute <aclrc@rit.edu>

var/spack/repos/builtin/packages/py-textual/package.py

@@ -0,0 +1,26 @@
+# Copyright 2013-2023 Lawrence Livermore National Security, LLC and other
+# Spack Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+
+from spack.package import *
+
+
+class PyTextual(PythonPackage):
+    """Textual is a Rapid Application Development framework for Python."""
+
+    homepage = "https://github.com/Textualize/textual"
+    pypi = "textual/textual-0.47.1.tar.gz"
+
+    version("0.47.1", sha256="4b82e317884bb1092f693f474c319ceb068b5a0b128b121f1aa53a2d48b4b80c")
+
+    depends_on("python@3.8:3", type=("build", "run"))
+
+    depends_on("py-poetry-core@1.2.0:", type="build")
+    depends_on("py-rich@13.3.3:", type=("build", "run"))
+    depends_on("py-markdown-it-py+linkify@2.1.0:", type=("build", "run"))
+    depends_on("py-mdit-py-plugins", type=("build", "run"))
+    # Depending on py-mdit-py-plugins rather than on py-markdown-it-py+plugins,
+    # because py-markdown-it-py+plugins would cause a circular dependency
+    depends_on("py-typing-extensions@4.4.0:4", type=("build", "run"))