python - Searching if the values on a list is in the dictionary whose format is key-string, value-list(strings) -

my_dict = {                              # dictionary generated thru 'a' : [ 'value1', 'value4', 'value5' ],  # info given user 'b' : [ 'value2', 'value6', 'value7'], 'c' : [ 'value3', 'value8', 'value9'] }  list = [ 'value1', 'value2' ] # list generated using list comprehension 

i need generate list output this:

output_list = ['a', 'b'] 

i need check if values on "list" matches values on list inside of dictionary. possible?

i tried use empty list:

[key key, value in my_dict.items() if value in list] 

you need iterate on list (and should not using list variable name, shadows built-in list function) . example -

[key item in lst key,value in my_dict.items() if item in value] 

demo -

>>> my_dict = {                              # dictionary generated thru ... 'a' : [ 'value1', 'value4', 'value5' ],  # info given user ... 'b' : [ 'value2', 'value6', 'value7'], ... 'c' : [ 'value3', 'value8', 'value9'] ... } >>> >>> lst = [ 'value1', 'value2' ] >>> [key item in lst key,value in my_dict.items() if item in value] ['a', 'b'] 

---

you can better performance, if use set instead of list store values in dictionary (since searching inside set o(1) operation, whereas searching inside list o(n) ). example -

my_dict = {key:set(value) key,value in my_dict.items()} [key item in lst key,value in my_dict.items() if item in value] 

demo -

>>> my_dict = {key:set(value) key,value in my_dict.items()} >>> pprint(my_dict) {'a': {'value4', 'value5', 'value1'},  'b': {'value6', 'value7', 'value2'},  'c': {'value3', 'value9', 'value8'}} >>> lst = [ 'value1', 'value2' ] >>> [key item in lst key,value in my_dict.items() if item in value] ['a', 'b'] 

---

if trying check if of values in list match value list in dictionary, can use set.intersection , check if result empty or not. example -

[key key, value in my_dict.items() if set(value).intersection(lst)] 

this result not ordered, since dictionary not have specific order.

demo -

>>> my_dict = { ... 'a' : [ 'value1', 'value4', 'value5' ], ... 'b' : [ 'value2', 'value6', 'value7'], ... 'c' : [ 'value3', 'value8', 'value9'] ... } >>> lst = [ 'value1', 'value2' ] >>> [key key, value in my_dict.items() if set(value).intersection(lst)] ['b', 'a']