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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 parse_vlan_range_mappings(mappings):
 """Parse vlan range mappings. Mappings must be a space-delimited list of provider:start:end mappings. The start:end range is optional and may be omitted. Returns dict of the form {provider: (start, end)}. """

    _mappings = parse_mappings(mappings)
    if not _mappings:
        return {}

    mappings = {}
    for p, r in six.iteritems(_mappings):
        mappings[p] = tuple(r.split(':'))

    return mappings