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Python

Posted by Sam Frampton
Sam Frampton
3,796 Points

Passed the section of the challenge but when running in a terminal it prints out individual letters rather than courses

'''teachers = {"eboni williams": "jenkins", "jillian mele": "python dev", "carley shimkus": "ruby dev", "hillary vaughn": "artificial intelligence", "lisa booth": "machine learning", "jedediah bilah": "jenkins", "emelie ikeda": "jenkins"}'''

''' def courses(teachers): course_list = [] for value in teachers.values(): course_list += value return course_list

print (courses(teachers)) '''

Returns

'''['a', 'r', 't', 'i', 'f', 'i', 'c', 'i', 'a', 'l', ' ', 'i', 'n', 't', 'e', 'l', 'l', 'i', 'g', 'e', 'n', 'c', 'e', 'j', 'e', 'n', 'k', 'i', 'n', 's', 'm', 'a', 'c', 'h', 'i', 'n', 'e', ' ', 'l', 'e', 'a', 'r', 'n', 'i', 'n', 'g', 'j', 'e', 'n', 'k', 'i', 'n', 's', 'p', 'y', 't', 'h', 'o', 'n', ' ', 'd', 'e', 'v', 'j', 'e', 'n', 'k', 'i', 'n', 's', 'r', 'u', 'b', 'y', ' ', 'd', 'e', 'v']'''

1 Answer

Ben Hedgepeth
seal-mask
.a{fill-rule:evenodd;}techdegree
Ben Hedgepeth
Python Web Development Techdegree Student 10,287 Points
Ben Hedgepeth
.a{fill-rule:evenodd;}techdegree
Ben Hedgepeth
Python Web Development Techdegree Student 10,287 Points

You are doing augmented assignment using two different types, list and str. What you are doing is this:

items = []

value = 'hello'

items = items + value # [] + ['h', 'e', 'l', 'l', 'o']

# items is now ['h', 'e', 'l', 'l', 'o']

In Python, a string is an immutable sequence. A list is also a sequence. In order to perform += operation, Python performs a coercion of sorts by spliting the string into a list of characters and extending the list to which you're attempting to add elements to. Instead of doing augmented addition, I would suggest using .append() within your for loop.