List Comprehension Error?

[gregcman]

y_train[y_train[:] == 1]
and
y_train[y_train[:] == 0]

both return 537 rows.

[ischoeff]

Yes can confirm that with docker jupyter/scipy-notebook:notebook-6.4.12.
It uses Python 3.10.6, pandas 1.5.0.
It works with:

print("Original True : {0} ({1:0.2f}%)".format(len(df.loc[df['diabetes'] == 1]), (len(df.loc[df['diabetes'] == 1])/len(df.index)) * 100.0))
print("Original False : {0} ({1:0.2f}%)".format(len(df.loc[df['diabetes'] == 0]), (len(df.loc[df['diabetes'] == 0])/len(df.index)) * 100.0))
print("")
print("Training True : {0} ({1:0.2f}%)".format(y_train.value_counts()[1], y_train.value_counts()[1] / y_train.size * 100))
print("Training False : {0} ({1:0.2f}%)".format(y_train.value_counts()[0], y_train.value_counts()[0] / y_train.size * 100))
print("")
print("Test True : {0} ({1:0.2f}%)".format(y_test.value_counts()[1], y_test.value_counts()[1] / y_test.size * 100))
print("Test False : {0} ({1:0.2f}%)".format(y_test.value_counts()[0], y_test.value_counts()[0] / y_test.size * 100))