Read VCF (vCard) contact export file and print phone numbers

parse_vcf.py

#!/bin/env python3
import sys

VCF_FILE = './contacts.vcf'

def main():
    alist = []

    with open(VCF_FILE, 'r') as f:
        vcard = None

        for line in f.readlines():
            line = line[:-1]

            if line == 'BEGIN:VCARD':
                vcard = {
                    'name': None,
                    'tels': []
                }

            elif vcard is None:
                print(f"File {VCF_FILE} is invalid", file=sys.stderr)
                return

            elif line == 'END:VCARD':
                if vcard['name'] is None or len(vcard['tels']) == 0:
                    print(f"Invalid VCARD: {repr(vcard)}", file=sys.stderr)

                else:
                    alist.append(vcard)
                    vcard = None

            elif line.startswith('FN:'):
                vcard['name'] = line[3:]

            elif line.startswith('FN;CHARSET=UTF-8'):
                _, val = line.split(':')
                vcard['name'] = decode_name(val)

            elif line.startswith('TEL;'):
                _, num = line[4:].split(':')
                vcard['tels'].append(num)

    if vcard is not None:
        print(f"Unterminated VCARD: {repr(vcard)}", file=sys.stderr)

    alist = sorted(alist, key=lambda v: v['name'])

    for vcard in alist:
        print(f"{vcard['name']}: {', '.join(vcard['tels'])}")

def decode_name(value):
    value = value.strip('=').split('=')
    out = bytearray([int(char, base=16) for char in value]).decode("UTF-8")
    return out

if __name__ == '__main__':
    main()