[Python] Unable to Check Dimensionality with Pint (DataFrame Elements)

I am trying to check the dimensionality of quantities passed to a function using the pint package. Specifically, I have a Pandas DataFrame where column data types are set using pint_pandas. I want to pass elements of this DataFrame to my function.

import pandas as pd
import pint
ureg = pint.UnitRegistry()
import pint_pandas

df = pd.DataFrame(
{
('range', 'km'): [200]
}
).pint.quantify(level=1)

@ureg.check(
'[length]',
)
def multiply_value(range):
return range * 2

multiply_value(df.iloc[0]['range'])


Unfortunately, this returns an error:

{
"name": "DimensionalityError",
"message": "Cannot convert from '200 kilometer' ([length]) to 'a quantity of' ([length])",
"stack": "---------------------------------------------------------------------------
DimensionalityError Traceback (most recent call last)
Cell In[100], line 18
12 @ureg.check(
13 '[mass]',
14 )
15 def multiply_value(range):
16 return range * 2
---> 18 multiply_value(df.iloc[0]['range'])

File /opt/homebrew/Caskroom/miniconda/base/envs/aircraft_performance/lib/python3.13/site-packages/pint/registry_helpers.py:381, in check.<locals>.decorator.<locals>.wrapper(*args, **kwargs)
379 if not ureg.Quantity(value).check(dim):
380 val_dim = ureg.get_dimensionality(value)
--> 381 raise DimensionalityError(value, \"a quantity of\", val_dim, dim)
382 return func(*args, **kwargs)

DimensionalityError: Cannot convert from '200 kilometer' ([length]) to 'a quantity of' ([length])"
}


If I instead define a pint quantity myself, it works just fine:

>>> range = 200 * ureg.km
>>> multiply_value(range)
400 kilometer

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