Keras-yolo3: Why use as Conv2D use_bias=not batch_normalize in Convert Model

[zhukkang]

in convert.py line 168 , why as batch_normalize on will set use_bias to False ?
conv_layer = (Conv2D(
filters, (size, size),
strides=(stride, stride),
kernel_regularizer=l2(weight_decay),
use_bias=not batch_normalize,
weights=conv_weights,
activation=act_fn,
padding=padding))(prev_layer)

[dzhus]

BatchNorm layers will shift activations by their mean values, so there's no point in adding any constants anyways – setting use_bias=False saves time and memory here.

[leoluopy]

BatchNorm layers will shift activations by their mean values, so there's no point in adding any constants anyways – setting use_bias=False saves time and memory here.

impressive answer