import re
import importlib

def is_valid_email(email):
    email_regex = r'^[a-zA-Z0-9_.+-]+@[a-zA-Z0-9-]+\.[a-zA-Z0-9-.]+$'
    return re.match(email_regex, email) is not None

def build_serializer_class(source):

    # Remove the 's' character at the end if present
    if source.endswith('s'):
        source = source[:-1]

    # Capitalize words separated by a dash
    words = source.split('-')
    capitalized_words = [word[0].upper() + word[1:] for word in words]
    transformed_string = ''.join(capitalized_words)

    # Add 'Serializer' at the end
    transformed_string += 'Serializer'

    module = importlib.import_module('api.serializers')
    return getattr(module, transformed_string)