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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 calldataload(computation: BaseComputation) -> None: """ Load call data into memory. """

    start_position = computation.stack_pop(type_hint=constants.UINT256)

    value = computation.msg.data_as_bytes[start_position:start_position + 32]
    padded_value = value.ljust(32, b'\x00')
    normalized_value = padded_value.lstrip(b'\x00')

    computation.stack_push(normalized_value)