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I'd like to use namedtuples internally, but I want to preserve compatibility with users that feed me ordinary tuples.
from collections import namedtuple tuple_pi = (1, 3.14, "pi") #Normal tuple Record = namedtuple("Record", ["ID", "Value", "Name"]) named_e = Record(2, 2.79, "e") #Named tuple named_pi = Record(tuple_pi) #Error TypeError: __new__() missing 2 required positional arguments: 'Value' and 'Name' tuple_pi.__class__ = Record TypeError: __class__ assignment: only for heap types 
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Tuples are immutable, whether named or not. namedtuple only makes the access more convenient, by using names instead of indices. You can only use valid identifiers for namedtuple , it doesn't perform any hashing — it generates a new type instead.
The accessing methods of NamedTuple From NamedTuple, we can access the values using indexes, keys and the getattr() method. The attribute values of NamedTuple are ordered. So we can access them using the indexes. The NamedTuple converts the field names as attributes.
To create a named tuple, import the namedtuple class from the collections module. The constructor takes the name of the named tuple (which is what type() will report), and a string containing the fields names, separated by whitespace. It returns a new namedtuple class for the specified fields.
You can use the *args call syntax:
named_pi = Record(*tuple_pi) This passes in each element of the tuple_pi sequence as a separate argument.
You can also use the namedtuple._make() class method to turn any sequence into an instance:
named_pi = Record._make(tuple_pi) Demo:
>>> from collections import namedtuple >>> Record = namedtuple("Record", ["ID", "Value", "Name"]) >>> tuple_pi = (1, 3.14, "pi") >>> Record(*tuple_pi) Record(ID=1, Value=3.14, Name='pi') >>> Record._make(tuple_pi) Record(ID=1, Value=3.14, Name='pi') If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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