change to forward reference for possibly unbound objects in type hint(s)

Author: pantheraleo-7

adafruit_ina219.py

@@ -33,14 +33,12 @@
 from micropython import const
 
 try:
-    import typing
+    from typing import TYPE_CHECKING
 
-    from busio import I2C
+    if TYPE_CHECKING:
+        from busio import I2C
 except ImportError:
-    # define I2C to avoid the error:
-    # def __init__(self, i2c_bus: I2C, addr: int = 0x40) -> None:
-    # NameError: name 'I2C' is not defined
-    I2C = None
+    pass
 
 __version__ = "0.0.0+auto.0"
 __repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_INA219.git"
@@ -153,7 +151,7 @@ class INA219:
     # raw_current                 RO : Current register (not scaled)
     # calibration                 RW : calibration register (note: value is cached)
 
-    def __init__(self, i2c_bus: I2C, addr: int = 0x40) -> None:
+    def __init__(self, i2c_bus: "I2C", addr: int = 0x40) -> None:
         self.i2c_device = I2CDevice(i2c_bus, addr)
         self.i2c_addr = addr