import boto3
import csv

client = boto3.client('lambda')

response = client.list_functions(
    MaxItems=123
)


lambdas = response['Functions']
lambdas_info= []

for function in lambdas:
    response_tags = client.list_tags(Resource=function['FunctionArn'])['Tags']
    tags = 'None'
    if 'application_family' in response_tags:
        tags = response_tags['application_family']
    lambdas_info.append({'Name': function['FunctionName'],
                         'Tags': tags})


service_columns = ['Name',  'Tags']
with open('lambdas.csv', 'w') as csvfile:
    writer = csv.DictWriter(csvfile, fieldnames=service_columns)
    writer.writeheader()
    writer.writerows(lambdas_info)