We saw previously how it was possible to ask at the REPL for help on Python functions. Let's look at how to add this self-documenting capability to our own module.
API documentation in Python uses a facility called docstrings. Docstrings are literal strings which occur as the first statement within a named block, such as a function or module. Let's document the fetch_words() function:
def fetch_words(url):
"""Fetch a list of words from a URL."""
with urlopen(url) as story:
story_words = []
for line in story:
line_words = line.decode('utf-8').split()
for word in line_words:
story_words.append(word)
return story_words
We use triple-quoted strings even for single-line docstrings because they can be easily expanded to add more detail.
One Python convention for docstrings...
