Describe the bug
Can't generate right doc string (parameters are omitted) when parameter has a default string containing python "reserved" words(like "class", "def", etc.)

Versions (please complete the following information):

• autoDocstring Version: v0.5.4
• Operating System: macOS Catalina 10.15.6 (19G2021)
• Vscode Version: 1.56.2

Original Code (with line to generate on):

def not_work(a="class"):
    pass

def work(a="clazz"):
    pass

Expected Result:

def not_work(a="class"):
    """[summary]

    Args:
        a (str, optional): [description]. Defaults to "class".
    """
    pass

def work(a="clazz"):
    """[summary]

    Args:
        a (str, optional): [description]. Defaults to "clazz".
    """
    pass

Actual Result:

def not_work(a="class"):
    """[summary]
    """
    pass

def work(a="clazz"):
    """[summary]

    Args:
        a (str, optional): [description]. Defaults to "clazz".
    """
    pass

Stack trace:
If an error was reported by autodocstring please copy the stack trace from the autoDocstring output channel.

no error was reported

Additional context
No additional context.