bring in CSV data into Pandas Dataframe

import pandas as pd
df = pd.read_csv('C:\Data\sample_data\california_housing_test.csv')
df

Select 3 columns into into a new dataframe

df1 = df[['longitude','latitude','housing_median_age']]
df1

A condition for values in one column

df1[df1['housing_median_age']==30]

A condition for values in more than one column. The AND operator.

df1[
(df1['housing_median_age']==30)
& (df1['latitude']>=38.00)
]

More than one condition in more than one column

Use one set of conditions or another. The OR operator.

Put this into a new dataframe df2

df2 = df1[
(df1['housing_median_age']==30)
& (df1['latitude']>=38.00)
|
(df1['housing_median_age']==40)
& (df1['latitude']>=38.00)
]
df2