What is the standard way for writing default values in a python docstring?

I have a function with parameters set to default values. I'm using a NumPy-style docstring, but I've seen the default values written elsewhere. What is the commonly accepted placement for writing "default" in the docstring?

def some_func(a_num=None, a_string=None):
    ''' A function that does something special.

    Parameters
    ==========
    a_num : int, default 100                        # is it written here?
        An important number.
    a_string : str, default 'foo'
        A useful string.  Default is 'foo'.         # or here?    
 
    '''

Solution 1:

If you read further in the document you linked it looks like there's no one standard style:

Optional keyword parameters have default values, which are displayed as part of the function signature. They can also be detailed in the description:

Description of parameter `x` (the default is -1, which implies summation
over all axes).

When a parameter can only assume one of a fixed set of values, those values can be listed in braces, with the default appearing first:

order : {'C', 'F', 'A'}
    Description of `order`.

I would recommending picking a style for your own project and sticking to it.