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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def add_sources_argument(cls, group, allow_filters=True, prefix=None, add_root_paths=False):
 """ Subclasses may call this to add sources and source_filters arguments. Args: group: arparse.ArgumentGroup, the extension argument group allow_filters: bool, Whether the extension wishes to expose a source_filters argument. prefix: str, arguments have to be namespaced. """

        prefix = prefix or cls.argument_prefix

        group.add_argument("--%s-sources" % prefix,
                           action="store", nargs="+",
                           dest="%s_sources" % prefix.replace('-', '_'),
                           help="%s source files to parse" % prefix)

        if allow_filters:
            group.add_argument("--%s-source-filters" % prefix,
                               action="store", nargs="+",
                               dest="%s_source_filters" % prefix.replace(
                                   '-', '_'),
                               help="%s source files to ignore" % prefix)

        if add_root_paths:
            group.add_argument("--%s-source-roots" % prefix,
                               action="store", nargs="+",
                               dest="%s_source_roots" % prefix.replace(
                                   '-', '_'),
                               help="%s source root directories allowing files "
                                    "to be referenced relatively to those" % prefix)