def override_dict(a, overrides):
    """Override a dict with another one **only first non nested keys**.

    Notes
    -----
    This works only with non-nested dict. If dictionarries are nested then the
    nested dict needs to be completly overriden.
    The Operation is performed inplace.

    Parameters
    ----------
    a : dict
        a dictionary to merge.
    overrides : dict
        another dictionary to merge.
    """
    for key, val in overrides.items():
        try:
            if type(a[key]) == dict:
                print(
                    "**warning**: key '{}' contained a dict make sure to override each value in the nested dict."
                    .format(key))
        except KeyError:
            pass
        a[key] = val
