{% extends "base/class.php.twig" %}

{% block file_path %}
Drupal\{{module}}\{{ class_name }}.
{% endblock %}

{% block namespace_class %}
namespace Drupal\{{module}};
{% endblock %}

{% block class_declaration %}
/**
 * Class {{ class_name }}.
 *
 * @package Drupal\{{module}}
 */
class {{ class_name }} {% if(interface) %}implements {{ class_name }}Interface{% endif %} {% endblock %}
{% block class_construct %}
  /**
   * Constructor.
   */
  public function __construct({{ servicesAsParameters(services)|join(', ') }}) {
{{ serviceClassInitialization(services) }}
  }
{% endblock %}

{% extends "base/class.php.twig" %}

{% block file_path %}
Drupal\{{module}}\{{ class_name }}.
{% endblock %}

{% block namespace_class %}
namespace Drupal\{{module}};
{% endblock %}

{% block class_declaration %}
/**
 * Class {{ class_name }}.
 *
 * @package Drupal\{{module}}
 */
class {{ class_name }}{% if(interface is defined and interface) %} implements {{ class_name }}Interface{% endif %} {% endblock %}
{% block class_construct %}
  /**
   * Constructor.
   */
  public function __construct({{ servicesAsParameters(services)|join(', ') }}) {
{{ serviceClassInitialization(services) }}
  }
{% endblock %}

Add proper space between Class name and implements keyword
Add proper space between Class name and implements keyword
