from typing import Sequence


def _isMonotonicUnique(l: Sequence[float]) -> bool:
    """
    Check that the provided sequence increases monotonically, and has no duplicates.
    """
    # we want to safely compare for equality. numpy/list semantics are different
    l = list(l)
    if len(set(l)) != len(l):
        # Duplicates
        return False

    # Assuming that we are going to fail anyways if this returns False, so be lazy and
    # compare to sorted list. Fast happy path.
    if sorted(l) != l:
        return False

    return True