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To select several keys into a new dictionary while skipping keys that are missing, use a dictionary comprehension: selected = {k: d[k] for k in keys if k in d}. If you need values in a list or tuple instead, choose a lookup that matches how missing keys should be handled.
Choose the result you need
Assume this dictionary and requested key list for the examples below:
d = {"name": "Ada", "age": 36, "city": "London"}
keys = ["name", "city", "country"]| Goal | Expression | Missing-key behavior | Order |
|---|---|---|---|
| New dictionary, omit missing keys | {k: d[k] for k in keys if k in d} |
Skips absent keys | Order of keys |
| List, use a fallback for missing keys | [d.get(k, None) for k in keys] |
Returns the specified default | Order of keys |
| List, require every key | [d[k] for k in keys] |
Raises KeyError if any key is absent |
Order of keys |
| Tuple, require every key | itemgetter(*keys)(d) |
Raises KeyError if any key is absent |
Order of keys |
| New dictionary, select by membership | {k: d[k] for k in d if k in wanted} |
Only keys present in d are selected |
Order of d |
Make a smaller dictionary and skip missing keys
Use a comprehension when you want a dictionary containing only the requested keys that exist:
selected = {k: d[k] for k in keys if k in d}
print(selected)
# {'name': 'Ada', 'city': 'London'}The if k in d check filters out "country" before the value lookup, so it cannot trigger a missing-key error. The result follows the order of keys, not the order of the source dictionary.
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Return values in a list
Use a default for absent keys
Call get() for each requested key when the result should have one value per requested key, even when some keys are absent:
values = [d.get(k, None) for k in keys]
print(values)
# ['Ada', 'London', None]Replace None with the fallback your code needs, such as an empty string or a numeric value. dict.get(key, default) returns that default when the key is missing rather than raising KeyError. See the Python 3.12 built-in types documentation.
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Require all requested keys
If an absent key indicates a problem and should stop execution, use subscription in a list comprehension:
values = [d[k] for k in keys]Every lookup uses d[k]. If even one requested key is absent, Python raises KeyError. This is useful when silently substituting a default or dropping a key would hide invalid input; the same subscription behavior is documented for Python dictionaries.
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Return a tuple with itemgetter
For a compact tuple of values when every key must exist, use operator.itemgetter:
from operator import itemgetter
values = itemgetter("name", "city")(d)
print(values)
# ('Ada', 'London')With multiple item names, itemgetter returns a tuple. It performs item access, so a missing key raises KeyError; choose the get() comprehension instead if you need defaults. The behavior is described in the Python 3.13 operator module documentation.
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Select keys by membership in the source dictionary
Sometimes you have a set of allowed keys and want to walk through the original dictionary, retaining matching entries:
wanted = {"name", "city"}
selected = {k: d[k] for k in d if k in wanted}This builds the result in the source dictionary’s key order, rather than the order of wanted. Python dictionaries preserve insertion order; use sorted(d) or sort the selected keys explicitly when sorted output is required. The Python data-structures tutorial shows dictionary iteration and sorted keys.
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Pick the missing-key policy deliberately
- Skip absent keys: use
{k: d[k] for k in keys if k in d}for a subset dictionary. - Keep a position for every requested key: use
[d.get(k, default) for k in keys]for a list with fallback values. - Treat absence as an error: use
d[k]in a list comprehension or useitemgetterfor a tuple. - Follow source dictionary order: iterate over
dand test membership in the wanted keys.
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