Python Function to Iterate over colums

 # Define count_entries()

def count_entries(csv_file,c_size,colname):

    """Return a dictionary with counts of

    occurrences as value for each key."""

    

    # Initialize an empty dictionary: counts_dict

    counts_dict = {}


    # Iterate over the file chunk by chunk

    for chunk in pd.read_csv(csv_file,chunksize=c_size):


        # Iterate over the column in DataFrame

        for entry in chunk[colname]:

            if entry in counts_dict.keys():

                counts_dict[entry] += 1

            else:

                counts_dict[entry] = 1


    # Return counts_dict

    return counts_dict


# Call count_entries(): result_counts

result_counts =count_entries('tweets.csv',10,'lang')


# Print result_counts

print(result_counts)

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