Comparisons and XML parsing

Author: crmpicco

coding-conventions.md

@@ -16,6 +16,18 @@
 
 The restricted line length originates from the early days of computing when terminals were limited to 80 characters per line. This convention is still followed in Python to ensure code readability across different editors and environments.
 
+### Comparisons
+Use `is` or `is not` when comparing to `None`. From a performance perspective, `is` is faster than `==` because it checks for object identity rather than value equality.
+```python
+crmpicco = None
+if crmpicco is None:
+    print("crmpicco is not here")
+
+the_champ = "cnation"
+if the_champ is not None:
+    print("the champ is here")
+``` 
+
 ### Types
 #### Informational
 Informational PEPs describe a Python design issue, or provide general guidelines or information to the Python community. Some examples of informational PEPs are [PEP-20](https://peps.python.org/pep-0020/) (The Zen of Python), and [PEP-257](https://peps.python.org/pep-0257/) (Docstring conventions).

network-programming.md

@@ -108,7 +108,30 @@ event_element = et.Element('event')
 print(type(event_element.attrib))
 # prints # <class 'dict'>
 ```
+`parse()` - used to parse an XML document from a string or a file. It returns an `ElementTree` object that represents the entire XML document.
 
+The following code parses an XML file and changes the tag of each child element to `football_competition`:
+```python
+import xml.etree.ElementTree as ET
+competitions = ET. parse('competitions.xml')
+root = competitions.getroot()
+for child in root:
+    child.tag = 'football_competition'
+```
+Sample XML file (`competitions.xml`):
+```xml
+<?xml version="1.0"?>
+<competitions>
+    <competition name="Scottish Cup">
+        <author>Scottish Football Association</author>
+        <year>1873</year>
+    </competition>
+    <competition name="Scottish League Cup">
+        <author>Scottish Professional Football League</author>
+        <year>1946</year>
+    </competition>
+</competitions>
+```
 ## General
 
 ### IP (Internet Protocol)