[Python] Arcpy manually assign class breaks

I want to have dynamic symbology by manually assigning values for class breaks:

• ≤ min
• min - max
• > max

I've come up with the function below, the issue is that it does not create the number of breaks that I want. Instead it created 4 class breaks using the with random class breaks.

def update_class_breaks(layer, breaks, classificationField):
min_val = float(breaks[0])
max_val = float(breaks[1])
sym = layer.symbology

if hasattr(sym, 'renderer') and sym.renderer.type == "GraduatedColorsRenderer":
sym.updateRenderer('GraduatedColorsRenderer')
renderer = sym.renderer
renderer.classificationField = classificationField
renderer.classificationMethod = 'Manual'
renderer.breakCount = 3

class_breaks = renderer.classBreaks

class_breaks[0].classMinValue = float('-inf')
class_breaks[0].classMaxValue = min_val

class_breaks[1].classMinValue = min_val
class_breaks[1].classMaxValue = max_val

class_breaks[2].classMinValue = max_val
class_breaks[2].classMaxValue = float('inf')

class_breaks[0].label = f"≤ {min_val}"
class_breaks[1].label = f"{min_val} - {max_val}"
class_breaks[2].label = f"> {max_val}"

layer.symbology = sym
else:
appLog.warning("Layer does not support GraduatedColorsRenderer or renderer missing.")

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