Why does Pandas df.head() show differently to to_csv export

I'm trying to scrape data from a few pages using pandas with some simple code.

import pandas as pd
import requests
import numpy as np

dfs = []

http = "https://www.milieudatabase.nl/viewNMD/view_materiaal_new.php?numCode="
for r in range(293,296):
    url = f'{http}{r:02d}'
   
    r = requests.get(url)
    df_list = pd.read_html(r.text) # this parses all the tables in webpages to a list
   
    dfs.append(df_list)
   
    
    NMD = pd.concat([pd.DataFrame(dfs)])
                    
print(NMD)

NMD.to_csv('NMD50.csv', index=False)
    
df.head()

When I use the df.head(), the dataframe displays in the way I would like. However, where I try and send this to csv it comes out with all data on 3 rows instead in the format of multiple rows. I think it's an issue with the df_list function,

Can anyone help?

Solution

You have couple of errors. First let me show the working code:

dfs = []

http = "https://www.milieudatabase.nl/viewNMD/view_materiaal_new.php?numCode="
for r in range(293,296):
    url = f'{http}{r:02d}'

    r = requests.get(url)
    df_list = pd.read_html(r.text) 

    dfs.append(df_list[0])
   

NMD = pd.concat(dfs)

You are adding list to list. But in reality, df_list has only 1 element.
Indentation error. You are creating NMD in every steps of the for loop.