title: drop function returning KeyError | Pandas
body: <p>I'm studying for a Data Science Olympiad competition and i have ran into a little problem. All ive done is converted values in a row with values ranging 2-8 into good or bad using a bin, then i used the label encoder to make them 1 or 0</p>
  
  <p>when running this code:</p>
  
  <pre><code>import pandas as pd
  import numpy as np
  from sklearn.ensemble import RandomForestClassifier
  from sklearn.model_selection import train_test_split
  from sklearn.preprocessing import StandardScaler, LabelEncoder
  
  #load our data file
  data = pd.read_csv("data.csv", delimiter=";")
  
  #classify wines as good or bad
  bins = (1,5,8)
  group_names = ['bad', "good"]
  data["quality"] = pd.cut(data["quality"], bins=bins, labels=group_names)
  print(data["quality"].unique())
  
  #list the labels as good or bad to 1 or 0
  label_quality = LabelEncoder()
  data["quality"] = label_quality.fit_transform(data["quality"])
  
  #create our feature ad result sets
  X = data.drop(data["quality"], axis=1)
  y = data["quality"]
  
  #create our training sets
  X_train, X_test, y_train, y_test = train_test_split(X, y, random_state=10)
  
  print(data.head(100))
  </code></pre>
  
  <p>i run into the error:</p>
  
  <pre><code>Traceback (most recent call last):
    File "main.py", line 21, in &lt;module&gt;    X = data.drop(data["quality"], axis=1)
    File "/home/runner/.local/share/virtualenvs/python3/lib/python3.8/site-packages/pandas/core/frame.py", line 3990, in drop    return super().drop(
    File "/home/runner/.local/share/virtualenvs/python3/lib/python3.8/site-packages/pandas/core/generic.py", line 3936, in drop    obj = obj._drop_axis(labels, axis, level=level, errors=errors)
    File "/home/runner/.local/share/virtualenvs/python3/lib/python3.8/site-packages/pandas/core/generic.py", line 3970, in _drop_axis    new_axis = axis.drop(labels, errors=errors)
    File "/home/runner/.local/share/virtualenvs/python3/lib/python3.8/site-packages/pandas/core/indexes/base.py", line 5018, in drop    raise KeyError(f"{labels[mask]} not found in axis")
  KeyError: '[0 0 0 ... 1 0 1] not found in axis'
  </code></pre>
  
  <p>it says my row values aren't found in the axis but i already specified axis one so shouldn't it cut it?</p>