import struct


def byte_to_float(b1, b2, b3, b4):
    """
    A function to get a 32 bit float from 4 bytes read in order [b1, b2, b3, b4]
    :param b1: first byte
    :param b2: second byte
    :param b3: third byte
    :param b4: fourth byte
    :return: the byte array from b1, b2, b3, b4 unpacked as a float using the 'struct' module
    """
    arr = bytearray([b1, b2, b3, b4])
    return struct.unpack('<f', arr)