Apply suggestions from code review

Co-authored-by: Fabian Fröhlich <fabian@schaluck.com>

doc/example/petab_import.ipynb

@@ -190,7 +190,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "Creating the objective from PEtab with default settings can be done in as many as two lines."
+    "Creating the objective from PEtab with default settings can be done in as little as two lines."
    ]
   },
   {
@@ -216,7 +216,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "If we need more flexibility, by defining whether you need residuals of the objective function, what sensitivities you want to use or fix certain parameters, you can also create the problem from a customized objective:"
+    "If you need more flexibility, e.g., to define whether you need residuals of the objective function, what sensitivities you want to use, or fix certain parameters, you can also create the problem from a customized objective:"
    ]
   },
   {