如何检查变量是否在python词典中的列表中？

Question

I'm writing a program to assign customer licenses. However, whenever the license in the database is changed it needs to change it in another program. However I'm having trouble because I nested a list inside of a dictionary and when I use if id in dictionary it doesn't find it even though I know its there for sure.

annotation = {'customer_id': 35, 'guest_os': 1287, 'license': [('VMware VM', 01), ('Veeam Backup VM', 02)]}

database_license = [('Veeam Backup VM', 02), ('VMware VM', 01)]

for product, license_id in annotation['license']:
    if license_id in database_license:
       print "do nothing"
    else:
       del annotation['license']
       annotation['license'] = database_license
       change = True

    if change == True:         
       annotation['license'] = license_check
       change_annotation(vm_mor, annotation)
       change = False    

for some reason that I can't seem to fix it will not find the value license_id inside the list database_licenses it just does the else, instead of print nothing.

Any ideas?

I want to use in because they could be out of order and therefor if you loop through both and use if ths id == that id it won't always work..

This is the working code:

 if str(vm_mor) == vm['config.annotation']:
    annotation= pickle.load(open(str(vm_mor), "rb"))
    print annotation

    sql_check_exist = '''select a.vm_mor, b.license_id, c.product from vms a , vm_licenses b, licenses c where a.vm_id = b.vm_id and b.license_id = c.license_id and a.vm_mor = '%s' ''' % str(vm_mor) 
    cursor_exist.execute(sql_check_exist)
    database_license = []

    for vm_mor, license_id, product in cursor_exist:
       database_license.append((product,license_id))

    checklist_database_license = [int(i[1]) for i in database_license] #make a list of 2nd element of all the tuples in the database_license list
    check_me = annotation['license']

    for product, license_id in check_me:
       if license_id in checklist_database_license:
          print "do nothing"
       else:
          del annotation['license']
          annotation['license'] = database_license
          change = True

    if change == True:         
       change_annotation(vm_mor, annotation)
       change = False    

 else:
    print vm['config.name']
    pickle_mor(vm_mor,vm) 

Answer 1

annotation['license'] is a list containing two tuples:

>>> annotation = {'customer_id': 35, 'guest_os': 1287, 'license': [('VMware VM', 01), ('Veeam Backup VM', 02)]}
>>> aList = annotation['license']
>>> aList[0]
('VMware VM', 1)
>>> aList[1]
('Veeam Backup VM', 2)
>>> (product, license_id) = aList[0]
>>> product
'VMware VM'
>>> license_id
1
>>>

Hope this clarifies the situation.

Answer 2

database_license = [('Veeam Backup VM', 02), ('VMware VM', 01)]
checklist_database_license = [int(i[1]) for i in database_license] #make a list of 2nd element of all the tuples in the database_license list

for product, license_id in annotation['license']:
    if license_id in checklist_database_license:
       print "do nothing"
    else:
       del annotation['license']
       annotation['license'] = database_license
       change = True

Answer 3

You've defined database_license as a list of tuples (pairs), so there's no way a string like 35 can be in it.

What you want to check is if any of the members have a matching id. Like this:

if any(product_license_id == license_id
       for product, license_id in database_license):

… or:

if product_license_id in map(itemgetter(1), database_license):

But maybe it would be better to store database_license as a dict , mapping license IDs to products:

database_license = {2: 'Veeam Backup', 1: 'VMWare VM'}

Then your existing code would work just fine.