We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
[Bug-Candidate]: Phi-node print missing 'f' in f-string
### Describe the issue:

When printing a Phi-node the string is not formatted.
There seems to be a 'f' missing ahead of the str in https://github.com/crytic/slither/blob/dev/slither/slithir/operations/phi.py#L36

### Code example to reproduce the issue:

slither tests/complex_func.sol --print slithir-ssa

### Version:

dev-branch dd91f770f61eaadc286e2af3c72fb5798e376c16

### Relevant log output:

```
Contract Increment
        Function Increment.increaseBy1()
                IRs:
                        {self.lvalue}({self.lvalue.type}) := ϕ({[str(v) for v in self._rvalues]})
                Expression: i += 1
```

--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `slither/slithir/operations/phi.py`
Content:
```
1 from slither.slithir.operations.lvalue import OperationWithLValue
2 from slither.slithir.utils.utils import is_valid_lvalue
3 
4 
5 class Phi(OperationWithLValue):
6     def __init__(self, left_variable, nodes):
7         # When Phi operations are created the
8         # correct indexes of the variables are not yet computed
9         # We store the nodes where the variables are written
10         # so we can update the rvalues of the Phi operation
11         # after its instantiation
12         assert is_valid_lvalue(left_variable)
13         assert isinstance(nodes, set)
14         super().__init__()
15         self._lvalue = left_variable
16         self._rvalues = []
17         self._nodes = nodes
18 
19     @property
20     def read(self):
21         return self.rvalues
22 
23     @property
24     def rvalues(self):
25         return self._rvalues
26 
27     @rvalues.setter
28     def rvalues(self, vals):
29         self._rvalues = vals
30 
31     @property
32     def nodes(self):
33         return self._nodes
34 
35     def __str__(self):
36         return "{self.lvalue}({self.lvalue.type}) := \u03D5({[str(v) for v in self._rvalues]})"
37
```
--- 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()

```

diff --git a/slither/slithir/operations/phi.py b/slither/slithir/operations/phi.py
--- a/slither/slithir/operations/phi.py
+++ b/slither/slithir/operations/phi.py
@@ -33,4 +33,4 @@
         return self._nodes
 
     def __str__(self):
-        return "{self.lvalue}({self.lvalue.type}) := \u03D5({[str(v) for v in self._rvalues]})"
+        return f"{self.lvalue}({self.lvalue.type}) := \u03D5({[str(v) for v in self._rvalues]})"

{"golden_diff": "diff --git a/slither/slithir/operations/phi.py b/slither/slithir/operations/phi.py\n--- a/slither/slithir/operations/phi.py\n+++ b/slither/slithir/operations/phi.py\n@@ -33,4 +33,4 @@\n         return self._nodes\n \n     def __str__(self):\n-        return \"{self.lvalue}({self.lvalue.type}) := \\u03D5({[str(v) for v in self._rvalues]})\"\n+        return f\"{self.lvalue}({self.lvalue.type}) := \\u03D5({[str(v) for v in self._rvalues]})\"\n", "issue": "[Bug-Candidate]: Phi-node print missing 'f' in f-string\n### Describe the issue:\n\nWhen printing a Phi-node the string is not formatted.\r\nThere seems to be a 'f' missing ahead of the str in https://github.com/crytic/slither/blob/dev/slither/slithir/operations/phi.py#L36\n\n### Code example to reproduce the issue:\n\nslither tests/complex_func.sol --print slithir-ssa\n\n### Version:\n\ndev-branch dd91f770f61eaadc286e2af3c72fb5798e376c16\n\n### Relevant log output:\n\n```\r\nContract Increment\r\n        Function Increment.increaseBy1()\r\n                IRs:\r\n                        {self.lvalue}({self.lvalue.type}) := \u03d5({[str(v) for v in self._rvalues]})\r\n                Expression: i += 1\r\n```\n", "before_files": [{"content": "from slither.slithir.operations.lvalue import OperationWithLValue\nfrom slither.slithir.utils.utils import is_valid_lvalue\n\n\nclass Phi(OperationWithLValue):\n    def __init__(self, left_variable, nodes):\n        # When Phi operations are created the\n        # correct indexes of the variables are not yet computed\n        # We store the nodes where the variables are written\n        # so we can update the rvalues of the Phi operation\n        # after its instantiation\n        assert is_valid_lvalue(left_variable)\n        assert isinstance(nodes, set)\n        super().__init__()\n        self._lvalue = left_variable\n        self._rvalues = []\n        self._nodes = nodes\n\n    @property\n    def read(self):\n        return self.rvalues\n\n    @property\n    def rvalues(self):\n        return self._rvalues\n\n    @rvalues.setter\n    def rvalues(self, vals):\n        self._rvalues = vals\n\n    @property\n    def nodes(self):\n        return self._nodes\n\n    def __str__(self):\n        return \"{self.lvalue}({self.lvalue.type}) := \\u03D5({[str(v) for v in self._rvalues]})\"\n", "path": "slither/slithir/operations/phi.py"}], "after_files": [{"content": "from slither.slithir.operations.lvalue import OperationWithLValue\nfrom slither.slithir.utils.utils import is_valid_lvalue\n\n\nclass Phi(OperationWithLValue):\n    def __init__(self, left_variable, nodes):\n        # When Phi operations are created the\n        # correct indexes of the variables are not yet computed\n        # We store the nodes where the variables are written\n        # so we can update the rvalues of the Phi operation\n        # after its instantiation\n        assert is_valid_lvalue(left_variable)\n        assert isinstance(nodes, set)\n        super().__init__()\n        self._lvalue = left_variable\n        self._rvalues = []\n        self._nodes = nodes\n\n    @property\n    def read(self):\n        return self.rvalues\n\n    @property\n    def rvalues(self):\n        return self._rvalues\n\n    @rvalues.setter\n    def rvalues(self, vals):\n        self._rvalues = vals\n\n    @property\n    def nodes(self):\n        return self._nodes\n\n    def __str__(self):\n        return f\"{self.lvalue}({self.lvalue.type}) := \\u03D5({[str(v) for v in self._rvalues]})\"\n", "path": "slither/slithir/operations/phi.py"}]}