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Given the following text problem statement, write Python code to implement the functionality described below in problem statement
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Problem:
I am trying to get count of letter chars in column using Pandas.
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Python Code:
import pandas as pd
df = pd.DataFrame({'str': ['Aa', 'Bb', '?? ?', '###', '{}xxa;']})
def g(df):
    df["new"] = df.apply(lambda p: sum(q.isalpha() for q in p["str"] ), axis=1)
    return df
df = g(df.copy())
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