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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_field(self, offset, length, format):
 """Returns unpacked Python struct array. Args: offset (int):
 offset to byte array within structure length (int):
 how many bytes to unpack format (str):
 Python struct format string for unpacking See Also: https://docs.python.org/2/library/struct.html#format-characters """

        return struct.unpack(format, self.data[offset:offset + length])[0]