I clearly see a positional argument defined, so why is it giving me this error?

I’m trying to condense my file format. I’ve changed the headers to match my function. It’s worked previously, but with this new file I’m getting a positional argument error.

input_fname = 'basic.xlsx'  # input filename
output_fname = 'basic-condensed.xlsx'  # output filename
basic_all = pd.read_excel(input_fname)

catalog_id_column = 'Product Number'
price_columns = 'List Price'
size_column = 'Size'

basic_all_condensed = condense_excel_multiprice(basic_all, price_columns, size_column)

writer = pd.ExcelWriter(output_fname,
                        engine='xlsxwriter',
                        options={'strings_to_urls': False})

gbio_abs_condensed.to_excel(writer, index=False, encoding='utf-8')
writer.close()

TypeError                                 Traceback (most recent call last)
<ipython-input-146-614ba8c55380> in <module>
     22 
     23 
---> 24 basicbio_all_condensed = condense_excel_multiprice(basicbio_all, price_columns, size_column)
     25 
     26 writer = pd.ExcelWriter(output_fname,

TypeError: condense_excel_multiprice() missing 1 required positional argument: 'size_column

>Solution :

Just because you have a variable called size_column doesn’t mean it was passed in the same/correct position that your function’s signature expected.

Take this example:

def foo(x, y, ax=None):
    return x + y

y = 1
foo(y)

This generates the error:

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-3-cf0d9fb1194f> in <module>
      3 
      4 y = 1
----> 5 foo(y)

TypeError: foo() missing 1 required positional argument: 'y'

That’s because I’m passing y as the first agrument, which my function refers to as x. Even though I passed y, I’m still missing one argument