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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 build_available_time_string(availabilities):
 """ Build a string eliciting for a possible time slot among at least two availabilities. """

    prefix = 'We have availabilities at '
    if len(availabilities) > 3:
        prefix = 'We have plenty of availability, including '

    prefix += build_time_output_string(availabilities[0])
    if len(availabilities) == 2:
        return '{} and {}'.format(prefix, build_time_output_string(availabilities[1]))

    return '{}, {} and {}'.format(prefix, build_time_output_string(availabilities[1]), build_time_output_string(availabilities[2]))