<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def parse_args(arglist, scheme):
 u""" Parse a list of arguments into a dict """

    arglist = [i for i in arglist if i.type != token.COMMA]

    ret_mapping = dict([(k, None) for k in scheme])

    for i, arg in enumerate(arglist):
        if arg.type == syms.argument and arg.children[1].type == token.EQUAL:
            # argument < NAME '=' any >
            slot = arg.children[0].value
            ret_mapping[slot] = arg.children[2]
        else:
            slot = scheme[i]
            ret_mapping[slot] = arg

    return ret_mapping