Consistent header decrease

lectures/python/packages_and_testing.ipynb

@@ -668,12 +668,12 @@
    "id": "13ff5249",
    "metadata": {},
    "source": [
-    "### Package name\n",
+    "## Package name\n",
     "\n",
     "As seen in the file above, we observe that we do not need to specify alot in the project description.\n",
     "We give the package a name, which should be reflected in `/src/pkg`. We use the source layout as it avoids some issues with a flat package structure, see [Python packaging guide](https://packaging.python.org/en/latest/discussions/src-layout-vs-flat-layout/) for more details.\n",
     "\n",
-    "### Author list\n",
+    "## Author list\n",
     "\n",
     "We create a list of authors with their name and email.\n"
    ]
@@ -692,7 +692,7 @@
    "id": "127f9e41",
    "metadata": {},
    "source": [
-    "### README\n",
+    "## README\n",
     "\n",
     "A package should have a description. This should be placed in a README file. The string should contain the local path (relative to the `pyproject.toml` file) to the description file.\n"
    ]
@@ -717,8 +717,13 @@
    "cell_type": "markdown",
    "id": "96749323",
    "metadata": {},
+   "source": []
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
    "source": [
-    "### Version\n",
+    "## Version\n",
     "\n",
     "Given a version number `MAJOR.MINOR.PATCH`, increment the:\n",
     "\n",
@@ -734,7 +739,7 @@
    "id": "5676816a",
    "metadata": {},
    "source": [
-    "### Python versioning\n",
+    "## Python versioning\n",
     "\n",
     "As Python evolves and introduces new features and deprecates versions, your software should do the same. Decide on a minimal requirement for Python (and in some cases a maximum version if a package you are using is not supporting the latest Python version).\n"
    ]
@@ -744,7 +749,7 @@
    "id": "79ce5039",
    "metadata": {},
    "source": [
-    "### Dependencies\n",
+    "## Dependencies\n",
     "\n",
     "As our package might depend on external software, we create a list of packages such as `[\"numpy>=1.21\", \"sklearn==1.3.0\"]` etc.\n",
     "These will be installed if not found on the system at the time of installation.\n"
@@ -755,7 +760,7 @@
    "id": "c1046053",
    "metadata": {},
    "source": [
-    "### Optional dependencies\n",
+    "## Optional dependencies\n",
     "\n",
     "Sometimes, we require dependencies for testing or development that are not requirements of the source code. We call these optional dependencies and list them as below\n"
    ]
@@ -896,7 +901,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.10.13"
+   "version": "3.8.10"
   },
   "widgets": {
    "application/vnd.jupyter.widget-state+json": {