def inspect_data(df, n=5):
    """
    Get first 'n' rows from dataframe, types of each feature,
    and sum of na values for each feature

    Parameters
    - df: (pandas dataframe) dataframe
    - n (default n=5): (int) num of rows to inspect 

    Return
    - df_sample, df_types, df_na: (tuple)
        df_sample: (pandas dataframe) dataframe with first n rows
        df_types: (pandas Series) series with features and respective types
        df_na: (pandas Series) series with number of na values in each feature
    """
    # Getting first n rows of dataframe
    df_sample = df.head(n)
    # Getting type of each feature
    df_types = df.dtypes
    # Getting na values
    df_na = df.isna().sum()

    return df_sample, df_types, df_na