I suggest adding this example to "6.4. Line width and line continuation". Method chaining is easier to read inside parentheses and one line per method.
import pandas as pd
import numpy as np
df = pd.DataFrame(
data={
"col0": [0, 0, 0, 0],
"col1": [0, 0, 0, 0],
"col2": [0, 0, 0, 0],
"col3": ["a", "b", "b", "a"],
"col4": ["alpha", "gamma", "gamma", "gamma"],
},
index=["row" + str(i) for i in range(4)],
)
# Chaining inside parentheses works
results = (df
.groupby(["col3", "col4"])
.agg({"col1": "count", "col2": "mean"})
)
print(results)
# Error: SyntaxError: invalid syntax
results = df
.groupby(["col3", "col4"])
.agg({"col1": "count", "col2": "mean"})
I suggest adding this example to "6.4. Line width and line continuation". Method chaining is easier to read inside parentheses and one line per method.