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diff --git a/slixmpp/util/stringprep_profiles.py b/slixmpp/util/stringprep_profiles.py
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+++ b/slixmpp/util/stringprep_profiles.py
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+# -*- coding: utf-8 -*-
+"""
+    slixmpp.util.stringprep_profiles
+    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+    This module makes it easier to define profiles of stringprep,
+    such as nodeprep and resourceprep for JID validation, and
+    SASLprep for SASL.
+
+    Part of Slixmpp: The Slick XMPP Library
+
+    :copyright: (c) 2012 Nathanael C. Fritz, Lance J.T. Stout
+    :license: MIT, see LICENSE for more details
+"""
+
+
+from __future__ import unicode_literals
+
+import stringprep
+from unicodedata import ucd_3_2_0 as unicodedata
+
+from slixmpp.util import unicode
+
+
+class StringPrepError(UnicodeError):
+    pass
+
+
+def b1_mapping(char):
+    """Map characters that are commonly mapped to nothing."""
+    return '' if stringprep.in_table_b1(char) else None
+
+
+def c12_mapping(char):
+    """Map non-ASCII whitespace to spaces."""
+    return ' ' if stringprep.in_table_c12(char) else None
+
+
+def map_input(data, tables=None):
+    """
+    Each character in the input stream MUST be checked against
+    a mapping table.
+    """
+    result = []
+    for char in data:
+        replacement = None
+
+        for mapping in tables:
+            replacement = mapping(char)
+            if replacement is not None:
+                break
+
+        if replacement is None:
+            replacement = char
+        result.append(replacement)
+    return ''.join(result)
+
+
+def normalize(data, nfkc=True):
+    """
+    A profile can specify one of two options for Unicode normalization:
+        - no normalization
+        - Unicode normalization with form KC
+    """
+    if nfkc:
+        data = unicodedata.normalize('NFKC', data)
+    return data
+
+
+def prohibit_output(data, tables=None):
+    """
+    Before the text can be emitted, it MUST be checked for prohibited
+    code points.
+    """
+    for char in data:
+        for check in tables:
+            if check(char):
+                raise StringPrepError("Prohibited code point: %s" % char)
+
+
+def check_bidi(data):
+    """
+    1) The characters in section 5.8 MUST be prohibited.
+
+    2) If a string contains any RandALCat character, the string MUST NOT
+       contain any LCat character.
+
+    3) If a string contains any RandALCat character, a RandALCat
+       character MUST be the first character of the string, and a
+       RandALCat character MUST be the last character of the string.
+    """
+    if not data:
+        return data
+
+    has_lcat = False
+    has_randal = False
+
+    for c in data:
+        if stringprep.in_table_c8(c):
+            raise StringPrepError("BIDI violation: seciton 6 (1)")
+        if stringprep.in_table_d1(c):
+            has_randal = True
+        elif stringprep.in_table_d2(c):
+            has_lcat = True
+
+    if has_randal and has_lcat:
+        raise StringPrepError("BIDI violation: section 6 (2)")
+
+    first_randal = stringprep.in_table_d1(data[0])
+    last_randal = stringprep.in_table_d1(data[-1])
+    if has_randal and not (first_randal and last_randal):
+        raise StringPrepError("BIDI violation: section 6 (3)")
+
+
+def create(nfkc=True, bidi=True, mappings=None,
+           prohibited=None, unassigned=None):
+    """Create a profile of stringprep.
+
+    :param bool nfkc:
+        If `True`, perform NFKC Unicode normalization. Defaults to `True`.
+    :param bool bidi:
+        If `True`, perform bidirectional text checks. Defaults to `True`.
+    :param list mappings:
+        Optional list of functions for mapping characters to
+        suitable replacements.
+    :param list prohibited:
+        Optional list of functions which check for the presence of
+        prohibited characters.
+    :param list unassigned:
+        Optional list of functions for detecting the use of unassigned
+        code points.
+
+    :raises: StringPrepError
+    :return: Unicode string of the resulting text passing the
+             profile's requirements.
+    """
+    def profile(data, query=False):
+        try:
+            data = unicode(data)
+        except UnicodeError:
+            raise StringPrepError
+
+        data = map_input(data, mappings)
+        data = normalize(data, nfkc)
+        prohibit_output(data, prohibited)
+        if bidi:
+            check_bidi(data)
+        if query and unassigned:
+            check_unassigned(data, unassigned)
+        return data
+    return profile