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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_nodes_section(f, current_section, nodes):
 """Parse TSPLIB NODE_COORD_SECTION or DEMAND_SECTION from file descript f Returns a dict containing the node as key """

    section = {}
    dimensions = None

    if current_section == 'NODE_COORD_SECTION':
        dimensions = 3 # i: (i, j)
    elif current_section == 'DEMAND_SECTION':
        dimensions = 2 # i: q
    else:
        raise ParseException('Invalid section {}'.format(current_section))

    n = 0
    for line in f:
        line = strip(line)

        # Check dimensions
        definitions = re.split(r'\s*', line)
        if len(definitions) != dimensions:
            raise ParseException('Invalid dimensions from section {}. Expected: {}'.format(current_section, dimensions))

        node = int(definitions[0])
        values = [int(v) for v in definitions[1:]]

        if len(values) == 1:
            values = values[0]

        section[node] = values

        n = n + 1
        if n == nodes:
            break

    # Assert all nodes were read
    if n != nodes:
        raise ParseException('Missing {} nodes definition from section {}'.format(nodes - n, current_section))

    return section