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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 _loop_payload(params):
    '''
    Pass in a dictionary of parameters, loop through them and build a payload containing,
    parameters who's values are not None.
    '''

    #construct the payload
    payload = {}

    #set the payload
    for param, value in six.iteritems(params):
        if value is not None:
            payload[param] = value

    return payload