human
Complete the below
def _concat_categorical(to_concat, axis=0):

    ''''Concatenate an object/categorical array of arrays, each of which is a
    single dtype
    Parameters
    to_concat : array of arrays
    axis : int
    Axis to provide concatenation in the current implementation this is
    always 0, e.g. we only have 1D categoricals
    Returns
    Categorical
    A single array, preserving the combined dtypes'
    '''
 What is a the Python program you requested?
assistant
#Here is the Python program you requested.
    def _concat_asobject(to_concat):
        to_concat = [(x.get_values() if is_categorical_dtype(x.dtype) else x.ravel()) for x in to_concat]
        res = _concat_compat(to_concat)
        if (axis == 1):
            return res.reshape(1, len(res))
        else:
            return res
    categoricals = [x for x in to_concat if is_categorical_dtype(x.dtype)]
    if (len(categoricals) != len(to_concat)):
        pass
    else:
        first = to_concat[0]
        if all((first.is_dtype_equal(other) for other in to_concat[1:])):
            return union_categoricals(categoricals)
    return _concat_asobject(to_concat)