Pandas KeyError: value not in index
<p>I have the following code, </p>

<pre><code>df = pd.read_csv(CsvFileName)

p = df.pivot_table(index=['Hour'], columns='DOW', values='Changes', aggfunc=np.mean).round(0)
p.fillna(0, inplace=True)

p[["1Sun", "2Mon", "3Tue", "4Wed", "5Thu", "6Fri", "7Sat"]] = p[["1Sun", "2Mon", "3Tue", "4Wed", "5Thu", "6Fri", "7Sat"]].astype(int)
</code></pre>

<p>It has always been working until the csv file doesn't have enough coverage (of all week days). For e.g., with the following .csv file, </p>

<pre><code>DOW,Hour,Changes
4Wed,01,237
3Tue,07,2533
1Sun,01,240
3Tue,12,4407
1Sun,09,2204
1Sun,01,240
1Sun,01,241
1Sun,01,241
3Tue,11,662
4Wed,01,4
2Mon,18,4737
1Sun,15,240
2Mon,02,4
6Fri,01,1
1Sun,01,240
2Mon,19,2300
2Mon,19,2532
</code></pre>

<p>I'll get the following error:</p>

<pre><code>KeyError: "['5Thu' '7Sat'] not in index"
</code></pre>

<p>It seems to have a very easy fix, but I'm just too new to Python to know how to fix it.</p>