what does the filter "in" do in django code example

Example 1: Django filters

import django_filters

class ProductFilter(django_filters.FilterSet):
  	# lookup_expr='iexact'
    # lookup_expr='icontains'
    name = django_filters.CharFilter(lookup_expr='iexact')

    class Meta:
        model = Product
        fields = ['price', 'release_date']

Example 2: django-filter

from django_filters import rest_framework as filters

class ProductFilter(filters.FilterSet):
    class Meta:
        model = Product
        fields = ('field')