prompt: We are currently solving the following issue within our repository. Here is the issue text:
  --- BEGIN ISSUE ---
  `Tuple[()]` is occasionally converted to `Tuple[Any, ...]`
  Most obvious when the `Tuple[()]` is passed through a Callable
  ```
  from typing import *
  
  Type = Callable[[Tuple[()]], int]
  x = "foo" # type: Type
  ```
  Results in:
  ```
  Incompatible types in assignment (expression has type "str", variable has type Callable[[Tuple[Any, ...]], int])
  ```
  
  As a side note,
  ```Type = Tuple[()]```
  Also appears to give a weird error.
  
  --- END ISSUE ---
  
  Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
  --- BEGIN FILES ---
  Path: `mypy/exprtotype.py`
  Content:
  ```
  1 """Translate an Expression to a Type value."""
  2 
  3 from mypy.nodes import (
  4     Expression, NameExpr, MemberExpr, IndexExpr, TupleExpr,
  5     ListExpr, StrExpr, BytesExpr, UnicodeExpr, EllipsisExpr
  6 )
  7 from mypy.parsetype import parse_str_as_type, TypeParseError
  8 from mypy.types import Type, UnboundType, TypeList, EllipsisType
  9 
  10 
  11 class TypeTranslationError(Exception):
  12     """Exception raised when an expression is not valid as a type."""
  13 
  14 
  15 def expr_to_unanalyzed_type(expr: Expression) -> Type:
  16     """Translate an expression to the corresponding type.
  17 
  18     The result is not semantically analyzed. It can be UnboundType or TypeList.
  19     Raise TypeTranslationError if the expression cannot represent a type.
  20     """
  21     if isinstance(expr, NameExpr):
  22         name = expr.name
  23         return UnboundType(name, line=expr.line, column=expr.column)
  24     elif isinstance(expr, MemberExpr):
  25         fullname = get_member_expr_fullname(expr)
  26         if fullname:
  27             return UnboundType(fullname, line=expr.line, column=expr.column)
  28         else:
  29             raise TypeTranslationError()
  30     elif isinstance(expr, IndexExpr):
  31         base = expr_to_unanalyzed_type(expr.base)
  32         if isinstance(base, UnboundType):
  33             if base.args:
  34                 raise TypeTranslationError()
  35             if isinstance(expr.index, TupleExpr):
  36                 args = expr.index.items
  37             else:
  38                 args = [expr.index]
  39             base.args = [expr_to_unanalyzed_type(arg) for arg in args]
  40             return base
  41         else:
  42             raise TypeTranslationError()
  43     elif isinstance(expr, ListExpr):
  44         return TypeList([expr_to_unanalyzed_type(t) for t in expr.items],
  45                         line=expr.line, column=expr.column)
  46     elif isinstance(expr, (StrExpr, BytesExpr, UnicodeExpr)):
  47         # Parse string literal type.
  48         try:
  49             result = parse_str_as_type(expr.value, expr.line)
  50         except TypeParseError:
  51             raise TypeTranslationError()
  52         return result
  53     elif isinstance(expr, EllipsisExpr):
  54         return EllipsisType(expr.line)
  55     else:
  56         raise TypeTranslationError()
  57 
  58 
  59 def get_member_expr_fullname(expr: MemberExpr) -> str:
  60     """Return the qualified name representation of a member expression.
  61 
  62     Return a string of form foo.bar, foo.bar.baz, or similar, or None if the
  63     argument cannot be represented in this form.
  64     """
  65     if isinstance(expr.expr, NameExpr):
  66         initial = expr.expr.name
  67     elif isinstance(expr.expr, MemberExpr):
  68         initial = get_member_expr_fullname(expr.expr)
  69     else:
  70         return None
  71     return '{}.{}'.format(initial, expr.name)
  72
  ```
  --- END FILES ---
  
  Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.
  
  Here is an example:
  
  ```diff
  diff --git a/examples/server_async.py b/examples/server_async.py
  --- a/examples/server_async.py
  +++ b/examples/server_async.py
  @@ -313,4 +313,4 @@
   
   
   if __name__ == "__main__":
  -    asyncio.run(run_async_server("."), debug=True)
  +    asyncio.run(run_async_server(), debug=True)
  diff --git a/examples/server_sync.py b/examples/server_sync.py
  --- a/examples/server_sync.py
  +++ b/examples/server_sync.py
  @@ -313,5 +313,5 @@
   
   
   if __name__ == "__main__":
  -    server = run_sync_server(".")
  +    server = run_sync_server()
       server.shutdown()
  
  ```
  
golden_diff: diff --git a/mypy/exprtotype.py b/mypy/exprtotype.py
  --- a/mypy/exprtotype.py
  +++ b/mypy/exprtotype.py
  @@ -37,6 +37,8 @@
               else:
                   args = [expr.index]
               base.args = [expr_to_unanalyzed_type(arg) for arg in args]
  +            if not base.args:
  +                base.empty_tuple_index = True
               return base
           else:
               raise TypeTranslationError()
  
verification_info: {"golden_diff": "diff --git a/mypy/exprtotype.py b/mypy/exprtotype.py\n--- a/mypy/exprtotype.py\n+++ b/mypy/exprtotype.py\n@@ -37,6 +37,8 @@\n             else:\n                 args = [expr.index]\n             base.args = [expr_to_unanalyzed_type(arg) for arg in args]\n+            if not base.args:\n+                base.empty_tuple_index = True\n             return base\n         else:\n             raise TypeTranslationError()\n", "issue": "`Tuple[()]` is occasionally converted to `Tuple[Any, ...]`\nMost obvious when the `Tuple[()]` is passed through a Callable\r\n```\r\nfrom typing import *\r\n\r\nType = Callable[[Tuple[()]], int]\r\nx = \"foo\" # type: Type\r\n```\r\nResults in:\r\n```\r\nIncompatible types in assignment (expression has type \"str\", variable has type Callable[[Tuple[Any, ...]], int])\r\n```\r\n\r\nAs a side note,\r\n```Type = Tuple[()]```\r\nAlso appears to give a weird error.\n", "before_files": [{"content": "\"\"\"Translate an Expression to a Type value.\"\"\"\n\nfrom mypy.nodes import (\n    Expression, NameExpr, MemberExpr, IndexExpr, TupleExpr,\n    ListExpr, StrExpr, BytesExpr, UnicodeExpr, EllipsisExpr\n)\nfrom mypy.parsetype import parse_str_as_type, TypeParseError\nfrom mypy.types import Type, UnboundType, TypeList, EllipsisType\n\n\nclass TypeTranslationError(Exception):\n    \"\"\"Exception raised when an expression is not valid as a type.\"\"\"\n\n\ndef expr_to_unanalyzed_type(expr: Expression) -> Type:\n    \"\"\"Translate an expression to the corresponding type.\n\n    The result is not semantically analyzed. It can be UnboundType or TypeList.\n    Raise TypeTranslationError if the expression cannot represent a type.\n    \"\"\"\n    if isinstance(expr, NameExpr):\n        name = expr.name\n        return UnboundType(name, line=expr.line, column=expr.column)\n    elif isinstance(expr, MemberExpr):\n        fullname = get_member_expr_fullname(expr)\n        if fullname:\n            return UnboundType(fullname, line=expr.line, column=expr.column)\n        else:\n            raise TypeTranslationError()\n    elif isinstance(expr, IndexExpr):\n        base = expr_to_unanalyzed_type(expr.base)\n        if isinstance(base, UnboundType):\n            if base.args:\n                raise TypeTranslationError()\n            if isinstance(expr.index, TupleExpr):\n                args = expr.index.items\n            else:\n                args = [expr.index]\n            base.args = [expr_to_unanalyzed_type(arg) for arg in args]\n            return base\n        else:\n            raise TypeTranslationError()\n    elif isinstance(expr, ListExpr):\n        return TypeList([expr_to_unanalyzed_type(t) for t in expr.items],\n                        line=expr.line, column=expr.column)\n    elif isinstance(expr, (StrExpr, BytesExpr, UnicodeExpr)):\n        # Parse string literal type.\n        try:\n            result = parse_str_as_type(expr.value, expr.line)\n        except TypeParseError:\n            raise TypeTranslationError()\n        return result\n    elif isinstance(expr, EllipsisExpr):\n        return EllipsisType(expr.line)\n    else:\n        raise TypeTranslationError()\n\n\ndef get_member_expr_fullname(expr: MemberExpr) -> str:\n    \"\"\"Return the qualified name representation of a member expression.\n\n    Return a string of form foo.bar, foo.bar.baz, or similar, or None if the\n    argument cannot be represented in this form.\n    \"\"\"\n    if isinstance(expr.expr, NameExpr):\n        initial = expr.expr.name\n    elif isinstance(expr.expr, MemberExpr):\n        initial = get_member_expr_fullname(expr.expr)\n    else:\n        return None\n    return '{}.{}'.format(initial, expr.name)\n", "path": "mypy/exprtotype.py"}], "after_files": [{"content": "\"\"\"Translate an Expression to a Type value.\"\"\"\n\nfrom mypy.nodes import (\n    Expression, NameExpr, MemberExpr, IndexExpr, TupleExpr,\n    ListExpr, StrExpr, BytesExpr, UnicodeExpr, EllipsisExpr\n)\nfrom mypy.parsetype import parse_str_as_type, TypeParseError\nfrom mypy.types import Type, UnboundType, TypeList, EllipsisType\n\n\nclass TypeTranslationError(Exception):\n    \"\"\"Exception raised when an expression is not valid as a type.\"\"\"\n\n\ndef expr_to_unanalyzed_type(expr: Expression) -> Type:\n    \"\"\"Translate an expression to the corresponding type.\n\n    The result is not semantically analyzed. It can be UnboundType or TypeList.\n    Raise TypeTranslationError if the expression cannot represent a type.\n    \"\"\"\n    if isinstance(expr, NameExpr):\n        name = expr.name\n        return UnboundType(name, line=expr.line, column=expr.column)\n    elif isinstance(expr, MemberExpr):\n        fullname = get_member_expr_fullname(expr)\n        if fullname:\n            return UnboundType(fullname, line=expr.line, column=expr.column)\n        else:\n            raise TypeTranslationError()\n    elif isinstance(expr, IndexExpr):\n        base = expr_to_unanalyzed_type(expr.base)\n        if isinstance(base, UnboundType):\n            if base.args:\n                raise TypeTranslationError()\n            if isinstance(expr.index, TupleExpr):\n                args = expr.index.items\n            else:\n                args = [expr.index]\n            base.args = [expr_to_unanalyzed_type(arg) for arg in args]\n            if not base.args:\n                base.empty_tuple_index = True\n            return base\n        else:\n            raise TypeTranslationError()\n    elif isinstance(expr, ListExpr):\n        return TypeList([expr_to_unanalyzed_type(t) for t in expr.items],\n                        line=expr.line, column=expr.column)\n    elif isinstance(expr, (StrExpr, BytesExpr, UnicodeExpr)):\n        # Parse string literal type.\n        try:\n            result = parse_str_as_type(expr.value, expr.line)\n        except TypeParseError:\n            raise TypeTranslationError()\n        return result\n    elif isinstance(expr, EllipsisExpr):\n        return EllipsisType(expr.line)\n    else:\n        raise TypeTranslationError()\n\n\ndef get_member_expr_fullname(expr: MemberExpr) -> str:\n    \"\"\"Return the qualified name representation of a member expression.\n\n    Return a string of form foo.bar, foo.bar.baz, or similar, or None if the\n    argument cannot be represented in this form.\n    \"\"\"\n    if isinstance(expr.expr, NameExpr):\n        initial = expr.expr.name\n    elif isinstance(expr.expr, MemberExpr):\n        initial = get_member_expr_fullname(expr.expr)\n    else:\n        return None\n    return '{}.{}'.format(initial, expr.name)\n", "path": "mypy/exprtotype.py"}]}