Raises TypeError if the array is not of an allowed dtype.

    :param array: array whose dtype is to be checked
    :param allowed: instance or list of allowed dtypes

def check_dtype(array, allowed):
    """Raises TypeError if the array is not of an allowed dtype.

    :param array: array whose dtype is to be checked
    :param allowed: instance or list of allowed dtypes
    """
    if not hasattr(allowed, "__iter__"):
        allowed = [allowed,]
    if array.dtype not in allowed:
        raise(TypeError(
            "Invalid dtype {}. Allowed dtype(s): {}".format(array.dtype, allowed)))