Fix KeyError when min_value or max_value are missing.

discord/commands/commands.py

@@ -528,8 +528,8 @@ def __init__(
             for o in kwargs.pop("choices", list())
         ]
         self.default = kwargs.pop("default", None)
-        self.min_value: Optional[Union[int, float]] = kwargs.pop("min_value")
-        self.max_value: Optional[Union[int, float]] = kwargs.pop("max_value")
+        self.min_value: Optional[Union[int, float]] = kwargs.pop("min_value", None)
+        self.max_value: Optional[Union[int, float]] = kwargs.pop("max_value", None)
 
         if any([self.max_value, self.min_value]) and not self.input_type in {SlashCommandOptionType.integer, SlashCommandOptionType.number}:
             raise TypeError('min_value and max_value can only be set on options with of type integer or number.')
@@ -544,9 +544,9 @@ def to_dict(self) -> Dict:
         }
         if self.channel_types:
             as_dict["channel_types"] = [t.value for t in self.channel_types]
-        if self.min_value:
+        if self.min_value is not None:
             as_dict["min_value"] = self.min_value
-        if self.max_value:
+        if self.max_value is not None:
             as_dict["max_value"] = self.max_value
 
         return as_dict