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# Im stuck here, i got the right answer, but it keep saying "Try again!"

Let's write some functions to explore set math a bit more. We're going to be using this COURSES dict in all of the examples. Don't change it, though! So, first, write a function named covers that accepts a single parameter, a set of topics. Have the function return a list of courses from COURSES where the supplied set and the course's value (also a set) overlap. For example, covers({"Python"}) would return ["Python Basics"].

sets.py
```COURSES = {
"Python Basics": {"Python", "functions", "variables",
"booleans", "integers", "floats",
"arrays", "strings", "exceptions",
"conditions", "input", "loops"},
"Java Basics": {"Java", "strings", "variables",
"input", "exceptions", "integers",
"booleans", "loops"},
"PHP Basics": {"PHP", "variables", "conditions",
"integers", "floats", "strings",
"booleans", "HTML"},
"Ruby Basics": {"Ruby", "strings", "floats",
"integers", "conditions",
"functions", "input"}
}
def covers(x):
courses_list = []
for course in COURSES:
if x.intersection(COURSES[course]):
courses_list.append(course)
return courses_list
```

Your append statement should be indented 1 more level so that it's part of the `if` statement.