def METHOD_NAME(token_stream, allow_functions=True):
    """yields tuples of TableReference namedtuples"""
    # We need to do some massaging of the names because postgres is case-
    # insensitive and '"Foo"' is not the same table as 'Foo' (while 'foo' is)
    def parse_identifier(item):
        name = item.get_real_name()
        schema_name = item.get_parent_name()
        alias = item.get_alias()
        if not name:
            schema_name = None
            name = item.get_name()
            alias = alias or name
        schema_quoted = schema_name and item.value[0] == '"'
        if schema_name and not schema_quoted:
            schema_name = schema_name.lower()
        quote_count = item.value.count('"')
        name_quoted = quote_count > 2 or (quote_count and not schema_quoted)
        alias_quoted = alias and item.value[-1] == '"'
        if alias_quoted or name_quoted and not alias and name.islower():
            alias = '"' + (alias or name) + '"'
        if name and not name_quoted and not name.islower():
            if not alias:
                alias = name
            # name = name.lower()
        return schema_name, name, alias
    for item in token_stream:
        if isinstance(item, IdentifierList):
            for identifier in item.get_identifiers():
                # Sometimes Keywords (such as FROM ) are classified as
                # identifiers which don't have the get_real_name() method.
                try:
                    schema_name = identifier.get_parent_name()
                    real_name = identifier.get_real_name()
                    is_function = allow_functions and _identifier_is_function(
                        identifier
                    )
                except AttributeError:
                    continue
                if real_name:
                    yield TableReference(
                        schema_name, real_name, identifier.get_alias(), is_function
                    )
        elif isinstance(item, Identifier):
            schema_name, real_name, alias = parse_identifier(item)
            is_function = allow_functions and _identifier_is_function(item)
            yield TableReference(schema_name, real_name, alias, is_function)
        elif isinstance(item, Function):
            schema_name, real_name, alias = parse_identifier(item)
            yield TableReference(None, real_name, alias, allow_functions)