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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 _serialize_linear_biases(linear, nodelist):
 """Serializes the linear biases. Args: linear: a interable object where linear[v] is the bias associated with v. nodelist (list):
 an ordered iterable containing the nodes. Returns: str: base 64 encoded string of little endian 8 byte floats, one for each of the biases in linear. Ordered according to nodelist. Examples: 'AAAAAAAA8L8AAAAAAADwPwAAAAAAAAAA' 'AAAAAAAAAAAAAAAAAADwPwAAAAAAAPC/' """

    linear_bytes = struct.pack('<' + 'd' * len(linear), *[linear[i] for i in nodelist])
    return base64.b64encode(linear_bytes).decode('utf-8')