import pandas as pd
def remove_purely_words(x):
if any(i.isdigit() for i in x):
return x
return None
df = pd.DataFrame({'Column2': ['Ser', 'DTR', 'Not123', '2345', 'Some text']})
df = df[df['Column2'].apply(remove_purely_words).notnull()]
print(df['Column2'].tolist())