f strings in core/series (#30025)

Author: donehower

pandas/core/series.py

@@ -104,9 +104,9 @@ def _coerce_method(converter):
     def wrapper(self):
         if len(self) == 1:
             return converter(self.iloc[0])
-        raise TypeError("cannot convert the series to {0}".format(str(converter)))
+        raise TypeError(f"cannot convert the series to {converter}")
 
-    wrapper.__name__ = "__{name}__".format(name=converter.__name__)
+    wrapper.__name__ = f"__{converter.__name__}__"
     return wrapper
 
 
@@ -274,8 +274,8 @@ def __init__(
                 try:
                     if len(index) != len(data):
                         raise ValueError(
-                            "Length of passed values is {val}, "
-                            "index implies {ind}".format(val=len(data), ind=len(index))
+                            f"Length of passed values is {len(data)}, "
+                            f"index implies {len(index)}."
                         )
                 except TypeError:
                     pass
@@ -1453,7 +1453,7 @@ def items(self):
         --------
         >>> s = pd.Series(['A', 'B', 'C'])
         >>> for index, value in s.items():
-        ...     print("Index : {}, Value : {}".format(index, value))
+        ...     print(f"Index : {index}, Value : {value}")
         Index : 0, Value : A
         Index : 1, Value : B
         Index : 2, Value : C
@@ -2160,7 +2160,7 @@ def corr(self, other, method="pearson", min_periods=None):
         raise ValueError(
             "method must be either 'pearson', "
             "'spearman', 'kendall', or a callable, "
-            "'{method}' was supplied".format(method=method)
+            f"'{method}' was supplied"
         )
 
     def cov(self, other, min_periods=None):
@@ -2876,7 +2876,7 @@ def _try_kind_sort(arr):
             sortedIdx[n:] = idx[good][argsorted]
             sortedIdx[:n] = idx[bad]
         else:
-            raise ValueError(f"invalid na_position: {repr(na_position)}")
+            raise ValueError(f"invalid na_position: {na_position}")
 
         result = self._constructor(arr[sortedIdx], index=self.index[sortedIdx])
 
@@ -3768,7 +3768,7 @@ def _reduce(
         elif isinstance(delegate, np.ndarray):
             if numeric_only:
                 raise NotImplementedError(
-                    "Series.{0} does not implement numeric_only.".format(name)
+                    f"Series.{name} does not implement numeric_only."
                 )
             with np.errstate(all="ignore"):
                 return op(delegate, skipna=skipna, **kwds)