Terraform Azurerm: Create blob if not exists - terraform

Question

I got Terrafrom code that creates storage account, container and block blob. Is it possible to configure that block blob is created only if it doesn't already exist?
In case of re-running terraform I wouldn't like to replace blob if it is already there as the content might have been manually modified and i would like to keep it.
Any tips? Only alternative I could think of is running powershell/bash script during further deployment steps that would create file if needed, but I am curious if this can be done just with Terraform.
locals {
storage_account_name_teast = format("%s%s", local.main_pw_prefix_short, "teast")
}
resource "azurerm_storage_account" "teaststorage" {
name = local.storage_account_name_teast
resource_group_name = azurerm_resource_group.main.name
location = var.location
account_tier = var.account_tier
account_replication_type = var.account_replication_type
allow_nested_items_to_be_public = false
min_tls_version = "TLS1_2"
network_rules {
default_action = "Deny"
bypass = [
"AzureServices"
]
virtual_network_subnet_ids = []
ip_rules = local.ip_rules
}
tags = var.tags
}
resource "azurerm_storage_container" "teastconfig" {
name = "config"
storage_account_name = azurerm_storage_account.teaststorage.name
container_access_type = "private"
}
resource "azurerm_storage_blob" "teastfeaturetoggle" {
name = "featureToggles.json"
storage_account_name = azurerm_storage_account.teaststorage.name
storage_container_name = azurerm_storage_container.teastconfig.name
type = "Block"
source = "vars-pr-default-toggles.json"
}

Answer 1

After scanning through terraform plan I figured out it was forcing a blob replacement because of:
content_md5 = "9a95db04fb1ff3abcd7ff81fcfb96307" -> null # forces replacement
I added lifecycle hook to blob resource to prevent it:
resource "azurerm_storage_blob" "teastfeaturetoggle" {
name = "featureToggles.json"
storage_account_name = azurerm_storage_account.teaststorage.name
storage_container_name = azurerm_storage_container.teastconfig.name
type = "Block"
source = "vars-pr-default-toggles.json"
lifecycle {
ignore_changes = [
content_md5,
]
}
}