Another rewarding day in the fast-paced world of WebDev. Man, you love your job! But as with any job, somtimes things can get a little tedious. Part of the website you're working on has a very repetitive structure, and writing all the HTML by hand is a bore. Time to automate! You want to write some functions that will generate the HTML for you. 
To organize your code, make of all your functions methods of a class called HTMLGen. Tag functions should be named after the tag of the element they create. Each function will take one argument, a string, which is the inner HTML of the element to be created. The functions will return the string for the appropriate HTML element.
For example, 
In JavaScript:
In Python:
```python
g = HTMLGen();
paragraph = g.p('Hello, World!')
block = g.div(paragraph)
# The following are now true
paragraph == 'Hello, World!'
block == 'Hello, World!'
```
Your HTMLGen class should have methods to create the following elements:
  * a
  * b
  * p
  * body
  * div
  * span
  * title
  * comment
Note: The comment method should wrap its argument with an HTML comment. It is the only method whose name does not match an HTML tag. So, ```g.comment('i am a comment')``` must produce ``````.
class Tag:

    def __init__(self, name):
        self.template = '<{0}>{{}}</{0}>'.format(name) if name != 'comment' else '<!--{}-->'
      
    __call__ = lambda self, content: self.template.format(content)


class HTMLGen:
    __getattr__ = lambda self, name: Tag(name)
class Tag:

    def __init__(self, name):
        self.template = '<{0}>{{}}</{0}>'.format(name) if name != 'comment' else '<!--{}-->'
      
    __call__ = lambda self, content: self.template.format(content)


class HTMLGen:
    __getattr__ = lambda self, name: Tag(name)