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Python Set Mutability: Deleting Elements

En-Wei Wright
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En-Wei Wright
Data Analysis Techdegree Graduate 8,796 Points
Posted by En-Wei Wright
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En-Wei Wright
Data Analysis Techdegree Graduate 8,796 Points

Example_2 and Example_3 in the exercise code

I think in the exercise code provided, example_2 and example_3 are missing the parentheses around the members in the set being compared to ({A, E, I, U} instead of {'A', 'E', 'I', 'U'})

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,426 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,426 Points

Hey En-Wei Wright, Can you expand on what you mean about the parentheses?

The curly brackets or braces { } define the set. A comma is used to separate the set elements. Any parens within the set definition would serve to define some element, such as a tuple, within the set. Any parens outside the set would serve to define the set itself as an element of a larger collection, or allow the set definition to span multiple lines.

In the later case, the parens are not part of the set definition but rather are part of the grouping syntax that allows for better readability:

# standard syntax
>>> s = {0, 1, 2, 3}
>>> s
{0, 1, 2, 3}

# grouping syntax 
>>> s = ({0, 1, 
2, 3})
>>> s
{0, 1, 2, 3}

# unnecessary grouping parens 
# ignored by parser
>>> s = ({0, 1, 2, 3})
>>> s
{0, 1, 2, 3}

Post back if you need more help. Good luck!!!