add docstring for python function in vim

docstring.vim

function! WriteParams()
    python << endpython
        import re
        import vim

        # get the function definition line
        line = vim.eval("getline(line('.'))")
        # get the number of spaces to add to the start of the line
        num_spaces = 4 + len(line) - len(line.lstrip())
        # get the line number wher to do the insertion
        line_number = int(vim.eval("line('.')"))

        # find the parameter names in the function definition
        params = re.findall("[\w=]+", line)[2:]

        # the header and the footer of the doctstring
        lines = ['"""', ""]

        for param in params:
            # skip the 'self' since it doesn't have to be documented.
            if param == "self":
                continue
            # handle the default argument parameters
            if "=" in param:
                param_name = param.split('=')[0]
                param_default_value = "".join(param.split('=')[1:])
                lines.append(":param %s: (Default value: %s)" % (param_name, param_default_value))
                lines.append(":type %s:" % param_name)
            else:
                lines.append(":param %s:" % param)
                lines.append(":type %s:" % param)

        lines.append(":returns:")
        lines.append('"""')
        # insert the contents of the list into the buffer
        vim.current.buffer[:] = vim.current.buffer[:line_number] + [(" "*num_spaces)+line for line in lines] + vim.current.buffer[line_number:] 
    endpython
endfunction