measurement_key(val: Any, default: Any = (, ))¶
Get the measurement key for the given value.
- val – The value which has the measurement key..
- default – Determines the fallback behavior when val doesn’t have a measurement key. If default is not set, a TypeError is raised. If default is set to a value, that value is returned if the value does not have _measurement_key_.
If val has a _measurement_key_ method and its result is not NotImplemented, that result is returned. Otherwise, if a default value was specified, the default value is returned.
TypeError– val doesn’t have a _measurement_key_ method (or that method returned NotImplemented) and also no default value was specified.