@classmethod
def check_required_modules(cls, mods):
    """Check that modules in `mods` list are available.

        Parameters
        ----------
        mods : list of str
            List of modules. Modules can have specified versions (eg 'numpy>=1.15')

        Returns
        -------
        bool
            True if all modules in list are available.
        """
    for mod in mods:
        if mod in cls._import_cache:
            if not cls._import_cache[mod]:
                return False
        if cls._module_checker.check(mod):
            cls._import_cache[mod] = True
        else:
            cls._import_cache[mod] = False
            return False
    return True
