input: Write a python function to get a post by its ID from a list of blog posts.
  assert get_post_by_id('1') == {'id': '1', 'title': 'Introducing my blog', 'content': 'This blog is all about my journey as a software developer.'}
  assert get_post_by_id('2') == {'id': '2', 'title': 'My First day', 'content': 'Today I created a website and wrote a few lines of code!'}
  assert get_post_by_id('3') == None
output: def get_post_by_id(post_id):
      blog_posts = [
          {'id': '1', 'title': 'Introducing my blog', 'content': 'This blog is all about my journey as a software developer.'},
          {'id': '2', 'title': 'My First day', 'content': 'Today I created a website and wrote a few lines of code!'}
      ]
      
      for post in blog_posts:
          if post['id'] == post_id:
              return post
      return None