Fixup comments and whitespace in generated Python code. (mozilla#2428)

This is purely aesthetic and has no functional changes.

uniffi_bindgen/src/bindings/python/templates/ExternalTemplate.py

@@ -1,20 +1,20 @@
 {%- let namespace = ci.namespace_for_type(type_)? %}
-{%- let module = python_config.module_for_namespace(namespace) -%}
+{%- let module = python_config.module_for_namespace(namespace) %}
 
 # External type {{ name }}: `from {{ module }} import {{ name }}`
 {%- let ffi_converter_name = "_UniffiConverterType{}"|format(name) %}
-{{ self.add_import_of(module, ffi_converter_name) }}
-{{ self.add_import_of(module, name) }} {#- import the type alias itself -#}
+{{- self.add_import_of(module, ffi_converter_name) }}
+{{- self.add_import_of(module, name) }} {#- import the type alias itself -#}
 
-# External type {{ name }} is an error.
 {%- if ci.is_name_used_as_error(name) %}
+# External type {{ name }} is an error.
 {%-     match type_ %}
 {%-         when Type::Object { .. } %}
 {%-             let err_ffi_converter_name = "{}__as_error"|format(ffi_converter_name) %}
-{{ self.add_import_of(module, err_ffi_converter_name) }}
+{{- self.add_import_of(module, err_ffi_converter_name) }}
 {%-         else %}
 {%-     endmatch %}
 {%- endif %}
 
 {%- let rustbuffer_local_name = "_UniffiRustBuffer{}"|format(name) %}
-{{ self.add_import_of_as(module, "_UniffiRustBuffer", rustbuffer_local_name) }}
+{{- self.add_import_of_as(module, "_UniffiRustBuffer", rustbuffer_local_name) }}