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diff --git a/mdit_py_plugins/attrs/index.py b/mdit_py_plugins/attrs/index.py
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+++ b/mdit_py_plugins/attrs/index.py
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+from typing import List, Optional
+
+from markdown_it import MarkdownIt
+from markdown_it.rules_inline import StateInline
+from markdown_it.token import Token
+
+from .parse import ParseError, parse
+
+
+def attrs_plugin(
+    md: MarkdownIt,
+    *,
+    after=("image", "code_inline", "link_close", "span_close"),
+    spans=False,
+    span_after="link",
+):
+    """Parse inline attributes that immediately follow certain inline elements::
+
+        ![alt](https://image.com){#id .a b=c}
+
+    This syntax is inspired by
+    `Djot spans
+    <https://htmlpreview.github.io/?https://github.com/jgm/djot/blob/master/doc/syntax.html#inline-attributes>`_.
+
+    Inside the curly braces, the following syntax is possible:
+
+    - `.foo` specifies foo as a class.
+      Multiple classes may be given in this way; they will be combined.
+    - `#foo` specifies foo as an identifier.
+      An element may have only one identifier;
+      if multiple identifiers are given, the last one is used.
+    - `key="value"` or `key=value` specifies a key-value attribute.
+       Quotes are not needed when the value consists entirely of
+       ASCII alphanumeric characters or `_` or `:` or `-`.
+       Backslash escapes may be used inside quoted values.
+    - `%` begins a comment, which ends with the next `%` or the end of the attribute (`}`).
+
+    Multiple attribute blocks are merged.
+
+    :param md: The MarkdownIt instance to modify.
+    :param after: The names of inline elements after which attributes may be specified.
+        This plugin does not support attributes after emphasis, strikethrough or text elements,
+        which all require post-parse processing.
+    :param spans: If True, also parse attributes after spans of text, encapsulated by `[]`.
+        Note Markdown link references take precedence over this syntax.
+    :param span_after: The name of an inline rule after which spans may be specified.
+    """
+
+    def _attr_rule(state: StateInline, silent: bool):
+        if state.pending or not state.tokens:
+            return False
+        token = state.tokens[-1]
+        if token.type not in after:
+            return False
+        try:
+            new_pos, attrs = parse(state.src[state.pos :])
+        except ParseError:
+            return False
+        token_index = _find_opening(state.tokens, len(state.tokens) - 1)
+        if token_index is None:
+            return False
+        state.pos += new_pos + 1
+        if not silent:
+            attr_token = state.tokens[token_index]
+            if "class" in attrs and "class" in token.attrs:
+                attrs["class"] = f"{attr_token.attrs['class']} {attrs['class']}"
+            attr_token.attrs.update(attrs)
+        return True
+
+    if spans:
+        md.inline.ruler.after(span_after, "span", _span_rule)
+    md.inline.ruler.push("attr", _attr_rule)
+
+
+def _find_opening(tokens: List[Token], index: int) -> Optional[int]:
+    """Find the opening token index, if the token is closing."""
+    if tokens[index].nesting != -1:
+        return index
+    level = 0
+    while index >= 0:
+        level += tokens[index].nesting
+        if level == 0:
+            return index
+        index -= 1
+    return None
+
+
+def _span_rule(state: StateInline, silent: bool):
+    if state.srcCharCode[state.pos] != 0x5B:  # /* [ */
+        return False
+
+    maximum = state.posMax
+    labelStart = state.pos + 1
+    labelEnd = state.md.helpers.parseLinkLabel(state, state.pos, False)
+
+    # parser failed to find ']', so it's not a valid span
+    if labelEnd < 0:
+        return False
+
+    pos = labelEnd + 1
+
+    # check not at end of inline
+    if pos >= maximum:
+        return False
+
+    try:
+        new_pos, attrs = parse(state.src[pos:])
+    except ParseError:
+        return False
+
+    pos += new_pos + 1
+
+    if not silent:
+        state.pos = labelStart
+        state.posMax = labelEnd
+        token = state.push("span_open", "span", 1)
+        token.attrs = attrs
+        state.md.inline.tokenize(state)
+        token = state.push("span_close", "span", -1)
+
+    state.pos = pos
+    state.posMax = maximum
+    return True