'Check that the pattern name does not contain a colon.'

def _check_pattern_name(self):

    if ((self.name is not None) and (':' in self.name)):
        warning = Warning("Your    URL    pattern    {}    has    a    name    including    a    ':'.    Remove    the    colon,    to    avoid    ambiguous    namespace    references.".format(self.describe()), id='urls.W003')
        return [warning]
    else:
        return []
