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diff --git a/share/extensions/barcode/Upce.py b/share/extensions/barcode/Upce.py
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+++ b/share/extensions/barcode/Upce.py
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+# coding=utf-8
+#
+# Copyright (C) 2010 Martin Owens
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA.
+#
+"""
+Python barcode renderer for UPCE barcodes. Designed for use with Inkscape.
+"""
+
+from .BaseEan import EanBarcode
+
+# This is almost exactly the same as the standard FAMILIES
+# But flipped around and with the first 111000 instead of 000000.
+FAMS = ['111000', '110100', '110010', '110001', '101100',
+        '100110', '100011', '101010', '101001', '100101']
+
+
+class Upce(EanBarcode):
+    """Generate EAN6/UPC-E barcode generator"""
+    name = 'upce'
+    font_size = 10
+    lengths = [6, 11]
+    checks = [7, 12]
+    center_bar = '020'
+
+    def _encode(self, num, guide=False):
+        """Generate a UPC-E Barcode"""
+        self.text = self.space(['0'], 2, num[:6], 2, num[-1])
+        code = self.encode_interleaved(num[-1], num[:6], FAMS)
+        return self.enclose(code)
+
+    def append_checksum(self, number):
+        """Generate a UPCE Checksum"""
+        if len(number) == 6:
+            number = self.convert_e2a(number)
+        result = self.get_checksum(number)
+        return self.convert_a2e(number) + result
+
+    def convert_a2e(self, number):
+        """Converting UPC-A to UPC-E, may cause errors."""
+        # All UPC-E Numbers use number system 0
+        if number[0] != '0' or len(number) != 11:
+            # If not then the code is invalid
+            raise ValueError("Invalid UPC Number")
+
+        # Most of the conversions deal
+        # with the specific code parts
+        maker = number[1:6]
+        product = number[6:11]
+
+        # There are 4 cases to convert:
+        if maker[2:] == '000' or maker[2:] == '100' or maker[2:] == '200':
+            # Maximum number product code digits can be encoded
+            if product[:2] == '00':
+                return maker[:2] + product[2:] + maker[2]
+        elif maker[3:5] == '00':
+            # Now only 2 product code digits can be used
+            if product[:3] == '000':
+                return maker[:3] + product[3:] + '3'
+        elif maker[4] == '0':
+            # With even more maker code we have less room for product code
+            if product[:4] == '0000':
+                return maker[0:4] + product[4] + '4'
+        elif product[:4] == '0000' and int(product[4]) > 4:
+            # The last recorse is to try and squeeze it in the last 5 numbers
+            # so long as the product is 00005-00009 so as not to conflict with
+            # the 0-4 used above.
+            return maker + product[4]
+        else:
+            # Invalid UPC-A Numbe
+            raise ValueError("Invalid UPC Number")
+
+    def convert_e2a(self, number):
+        """Convert UPC-E to UPC-A by padding with zeros"""
+        # It's more likly to convert this without fault
+        # But we still must be mindful of the 4 conversions
+        if len(number) != 6:
+            return None
+
+        if number[5] in ['0', '1', '2']:
+            return '0' + number[:2] + number[5] + '0000' + number[2:5]
+        elif number[5] == '3':
+            return '0' + number[:3] + '00000' + number[3:5]
+        elif number[5] == '4':
+            return '0' + number[:4] + '00000' + number[4]
+        else:
+            return '0' + number[:5] + '0000' + number[5]